The R740 is a 2U server from Dell compatible with Intel Xeon Scalable processors. The platform supports a wide range of configuration options, including several different front-drive configurations. The server we’ll focus on today is the Dell PowerEdge R740 8 Bay Small Form Factor, which supports up to eight 2.5-inch SAS or SATA hard drives and solid-state drives through the front drive bays. This particular configuration does not support NVMe drives in the front bays, nor does the R740 support the mid-bay or rear storage options found on the R740xd.

Essential Components

Before you begin assembling an R740 from an empty chassis, it is important to identify the hardware required to turn the chassis into a functioning server. This section covers the major components that should be installed and verified before moving on to the rest of the build.

The goal is to start with a bare chassis and make sure you have everything necessary to power the system on, recognize the installed hardware, and eventually install an operating system.

Motherboard

The motherboard should already be installed in the chassis and securely fastened in place. It serves as the central connection point for nearly all of the server’s hardware.

The processors and memory modules are installed directly onto the motherboard, while the power supplies connect to it through the rear of the chassis. PCIe risers attach to the motherboard to provide expansion slots, and the front storage backplane connects to the system board and storage controller. The hot-swap fan assembly also connects to the motherboard.

Before installing additional components, make sure the motherboard is properly seated and secured inside the chassis. A loose or incorrectly installed system board can prevent the server from powering on or cause other hardware to malfunction.

Backplane and Cables

The front storage backplane is another critical component of the R740 8-bay configuration. It provides the connections that allow the front-mounted drives to communicate with the server’s storage controller while also supplying power to the drive bays.

The backplane requires several connections to operate correctly. These include the signal cable, which connects the backplane to the motherboard, and the power cable, which supplies electrical power to the backplane. A SAS PERC or PCIe cable is also required to connect the backplane to the server’s RAID or HBA controller.

For the R740 8-bay configuration, pay particular attention to the specific cables required for the backplane and the storage controller installed in your system. Dell used different cable assemblies depending on the chassis and storage configuration, so having a cable that physically fits does not necessarily mean it is the correct cable for the configuration.

Before proceeding with the build, inspect the backplane and confirm that the required signal, power, and SAS connections are present and properly seated. These connections are essential for the server to detect and communicate with the drives installed in the front
bays.

Click to see picture of backplane

Click to see picture of backplane signal cable

Click to see picture of backplane power cable

Click to see picture of PCIe SAS storage cable

Cooling

The R740 uses a combination of fans, processor heatsinks, and an air shroud to maintain proper operating temperatures throughout the system. These components work together to move air through the chassis and remove heat from the processors, memory, and other internal hardware.

The fan modules are the most visible part of the cooling system. The fans first install into an assembly cage before the entire unit is placed into the chassis and locked into place. Like many other Dell PowerEdge servers, the R740 uses orange fan housings to identify hot-swappable components.

The R740 is available with both standard-performance and high-performance fan modules. The correct fan type depends on the hardware configuration and thermal requirements of the system. Higher-powered processors (>165W TDP) and other configurations with greater thermal demands may require the high-performance fans. While not applicable to the R740 8 Bay model, installation of a rear flex bay on the R740xd also requires high performance fans. Using standard performance fans when the configuration requires high performance can result in excessive RPM and a lot more noise from the server. With this particular model the only specification you should pay attention to is the TDP of your processor. Since this model does not support NVME or extra storage flex bays these configurations won’t be taken into consideration.

All six fan modules should be installed for normal operation of the R740. The server’s fan configuration is different from the R640, so make sure you are using the correct number and type of fans for the R740 chassis. Running the system with missing fans can result in cooling problems, system warnings, or logged hardware errors. A missing fan will cause the other fans to spin faster.

The processors also require compatible heatsinks. A system with two processors will need two heatsinks, with standard and high-performance options available. Standard heatsinks are low profile and use an aluminum construction, while high-performance heatsinks use a copper contact surface to improve heat transfer from the processor.

The appropriate heatsink should be matched to the processor and overall system configuration. Each heatsink also includes a black plastic retention clip on its underside. This clip secures the processor against the heatsink and helps maintain the proper position during installation. The retention clip is part of the heatsink assembly and should remain installed.

The R740 actually supports 3 different kinds of heatsinks. Because of its 2U design it not only supports the low/high performance heatsinks compatible with 1U systems like the R640, but also 2U high performance heatsinks made specifically by Dell for their 2U servers.

Click to see standard performance 1U heatsinks

Click to see high performance 1U heatsinks

The final major component of the R740’s cooling system is the air shroud. Positioned over the motherboard, the shroud helps channel airflow from the fan assembly through the areas containing the processors, memory, and other heat-producing components. Operating the server without the shroud can disrupt the intended airflow pattern and reduce cooling performance.

The fans, processor heatsinks, and air shroud are all essential parts of the R740’s thermal management system. Before powering on a server assembled from an empty chassis, verify that the appropriate fan modules and heatsinks are installed and that the air shroud is securely in place.

Risers

The R740 has many options for risers. Some risers (riser 1 as an example) have multiple variations. Certain variations prevent the installation of components like the Dell Mini Mono RAID/HBA controller. In this section we will discuss the options and features of the available risers for the R740 platform. Risers compatible with the R740 are also compatible with the R740xd.

Expansion Card Riser	PCIe Slot	Height	Length	Link
Riser 1A	Slot 1	Full Height	Full Length	x16
	Slot 3	Full Height	Half Length	x16
Riser 1B	Slot 1	Full Height	Full Length	x8
	Slot 2	Full Height	Full Length	x8
	Slot 3	Full Height	Half Length	x8
Riser 1D	Slot 1	Full Height	Full Length	x16
	Slot 2	Full Height	Full Length	x8
	Slot 3	Full Height	Half Length	x8
Riser 2A or 2E	Slot 4	Full Height	Full Length	x16
	Slot 5	Full Height	Full Length	x8
	Slot 6	Low Profile	Half Length	x8
Riser 2B	Slot 4	Low Profile	Half Length	x8
Riser 2C	Slot 4	Low Profile	Half Length	x16
Riser 3A or 3B	Slot 7	Full Height	Full Length	x8
	Slot 8	Full Height	Full Length	x16

 

Riser 1A

Click to see Riser 1B

Click to see Riser 1D

Riser 2A

Riser 2A is a 3 slot riser with two x8 slots and a single x16 slot at the top. If your chassis does not have this riser you may have one of the low profile risers below. Low profile risers are not that relevant for this particular server unless you’re selecting a riser based on the cost of buying second hand. For the R740xd they’re more relevant because you cannot use Riser 2A with something like a rear flex bay. If such a flex bay is used, a low profile riser can be installed to add an additional x8 or x16 slot to the server.The R740 8 bay SFF server does not allow for a rear flex bay so it makes more sense to install riser 2A and forget about the low profile risers.

Click to see Riser 2B

Click to see Riser 2C

Riser 3 A/B

Building the Server

Once you have confirmed that the R740 chassis contains the necessary hardware, you can begin assembling the system. Before installing every component, it is a good idea to perform an initial power-on test using only the hardware required for the server to complete POST.

At a minimum, the system will need:

• At least one CPU
• Memory
• At least one power supply

Required Tools

Tools needed to build a Dell PowerEdge R740

Fortunately, assembling the R740 does not require a large collection of specialized tools. You should have a Phillips #2 screwdriver, a T30 Torx bit, thermal paste, and either an electric air blower or a can of compressed air available before beginning the build.

Keep in mind that the R740 can operate with a single processor, but doing so limits some of the server’s functionality. Certain PCIe slots and risers are connected to CPU2 and will not be available when the second processor is not installed. If you plan to use additional expansion cards, verify the PCIe slot configuration before deciding to build the server with only one CPU.

Installing the Processors

The R740 has two processor sockets located near the center of the motherboard, identified as CPU1 and CPU2. Depending on the condition of the chassis, the sockets may already contain processors and heatsinks, or they may be covered by protective CPU socket covers.

If you are installing a processor into a previously used system, first remove the existing heatsink and processor if necessary. If the socket is empty, remove the protective socket cover before installing the CPU. Make careful note of the orientation arrows. The processor can only install one way. Installing the processor upside down can damage the CPU pins and render the server unusable. Blow out any dust that could be in the sockets.

Take care when working around the processor sockets. The socket contains delicate contacts that can be damaged if the processor or surrounding hardware is handled improperly. Avoid touching the contacts and make sure the processor is correctly oriented before securing it in the socket.

The R740 uses a processor retention mechanism that secures the CPU in place before the heatsink is installed. Once the processor is seated correctly, apply the appropriate thermal paste and install the corresponding heatsink.

If you are building a dual-processor system, repeat the procedure for CPU2, using a processor supported by the same generation and configuration as CPU1.

Installing the Memory

The R740 has six memory channels per processor, with two DIMM slots available on each channel. This gives each processor access to 12 DIMM slots, for a total of 24 DIMM slots in a dual-processor configuration.

The R740 uses white DIMM slots as the primary slots and black slots as the secondary slots. When installing memory, populate the primary white slots in each memory channel before adding DIMMs to the secondary black slots.

For the best memory performance, distribute DIMMs across as many memory channels as possible rather than installing two DIMMs in a single channel while leaving other channels unused. In a dual-processor system, memory should also be distributed evenly between CPU1 and CPU2 whenever possible.

For example, if you have eight identical DIMMs to install in a dual-processor R740, a balanced configuration would be to install four DIMMs on CPU1 and four on CPU2, using the primary slots in each processor’s memory channels.

When adding memory to an existing configuration, try to maintain the same DIMM capacity, rank characteristics, and memory type across corresponding channels. The R740 supports DDR4 ECC RDIMMs and LRDIMMs, but RDIMMs and LRDIMMs should not be mixed within the same system.

Click here to view the R740 memory channel mapping

CPU (Socket)	Memory Channel	Primary DIMM (1 DPC)	Secondary DIMM (2 DPC)
Socket 01 (CPU1)	Channel 0	A1	A7
	Channel 1	A2	A8
	Channel 2	A3	A9
	Channel 3	A4	A10
	Channel 4	A5	A11
	Channel 5	A6	A12
Socket 02 (CPU2)	Channel 0	B1	B7
	Channel 1	B2	B8
	Channel 2	B3	B9
	Channel 3	B4	B10
	Channel 4	B5	B11
	Channel 5	B6	B12

Here I have a total of 4 sticks of RAM. I will evenly distribute 2 of them to CPU1 and another 2 to CPU 2. (A1, A2, B1, B2) In Dell systems, A represents CPU1 and B represents CPU2. If you have trouble finding the DIMMs you can refer to your servers air shroud.

Installing the NDC

The NDC or network daughter card provides the server with various network ports and speeds depending on the exact part. The installation is the exact same no matter which NDC you have.

Start by removing riser 2. This will expose the proprietary Dell Mezzanine port.

Installing a RAID or HBA controller

If you have storage drives and you want them exposed to the system you will need to install a RAID or HBA controller. An HBA controller will simply pass the drives through to whatever operating system you are running. If you have a RAID controller you will need to configure the drives as part of a RAID array. Even a single drive must have a RAID 0 applied to it. Alternatively, a RAID controller can also be configured to operate in HBA mode, although this is usually not recommended especially if you plan on using software RAID solutions like ZFS.

There are 2 types of controllers you can install in the R740. The first type is a PCIe controller. This type of controller installs into any standard PCIe slot. In this case, the card will install into of the risers. Riser 2 is the recommended riser to install such a card. The second type of card is a mini mono card. This card has a proprietary connection to the motherboard. Functionally, both these cards are the same. The advantage of the mini mono controller is it doesn’t take up a PCIe slot in the risers. It is still a PCIe device at the core but its connection to the system is different than a typical PCIe card.

We will cover the installation of both types of cards.

Click for PCIe RAID/HBA instructions

Click for mini mono RAID/HBA instructions

Installing the power supplies

Lastly, we will install the power supplies. This is a pretty easy step. Grab a power supply and either reach over the server and slide them through the rear slots or walk around to the back. There are 2 slots for power supplies and they slide in. When sliding them in apply a bit more pressure at the end to ensure they properly connect to the motherboard.

The Dell PowerEdge R640 10 Bay is one of the most popular server platforms that came out of the Intel Xeon Scalable generation. It features 10 SFF drive bays in the front. Unlike the 8 bay model, the 10 bay does have support for NVME drives. This makes the R640 10 bay an extremely versatile 1U server chassis. In the rear it can be configured with 3 half height expansion slots or 2 full height slots. Configuration depends entirely on chassis selection and riser setup. The most common configuration is 3 half height rear chassis.

Essential components

When assembling this server from an empty chassis, there are several essential components that need to be identified and verified before you begin. This guide is intended for anyone who has a server chassis in front of them and wants to turn it into a working system, but may not be familiar with the hardware or know exactly what is needed to get the server powered on and running a functional operating environment.

Motherboard

The chassis should already have the motherboard securely installed. The motherboard is the primary hub of the server, with virtually every other component connecting to it in some way. The power supplies connect to the motherboard from the rear of the chassis, while the processors and memory are installed directly on the board. The PCIe risers connect to their respective slots, the backplane is wired to allow drives to be installed from the front of the chassis, and the hot-swap fans connect directly to the motherboard.

Before continuing, verify that the motherboard is properly installed and secured inside the chassis.

Backplane and Required Cables

The second, and perhaps less obvious, piece of hardware you will need is the backplane, along with the required cables used to connect it to the motherboard and storage controller.

In most configurations, a backplane will require three separate connections. This also applies to rear flex-bay backplanes. The first is the signal cable, which connects the backplane to the system board. The second is the power cable, which supplies power to the backplane. The third is the SAS PERC cable, which connects the backplane to the RAID or HBA controller.

With this particular chassis, you will most likely be using one of Dell’s PERC cables to connect the backplane to a Mini Mono RAID/HBA controller. The 10 Bay model has a  second power cable that supplies power to the expansion board.

Take a close look at the backplane and verify that all four required cables are present and properly connected. Without the necessary signal, power, and SAS connections, the server will not be able to properly communicate with or manage the installed drives.

Click to see picture of signal cable

Click to see picture of backplane power cable

Click to see picture of backplane expansion power cable

Click to see picture of PERC cable

Cooling

Proper cooling is essential to the operation of the R640, and several components work together to keep the processors and other internal hardware within their required operating temperatures.

The most obvious of these components are the cooling fans, highlighted in orange in the image above. On Dell servers, orange is generally used to identify components that are designed to be hot-swappable.

The fans slide into their designated positions in the chassis and make electrical contact with the motherboard through a set of pins. The R640 uses two different fan types: standard-performance and high-performance fans. The appropriate fan type depends on the server’s configuration. High-performance fans are recommended when using processors with a TDP above 165 watts, while standard-performance fans are suitable for lower-power configurations.

Regardless of which fan type you use, the chassis should have all 8 fan modules installed. Operating the server without the complete fan complement can result in hardware warnings and logged errors and may also lead to inadequate cooling under load.

The processors also require appropriate heatsinks. A dual-processor configuration will require two heatsinks, with the same standard and high-performance options available. Standard heatsinks are constructed entirely from aluminum, while high-performance heatsinks incorporate a copper contact surface to improve heat transfer away from the processor.

Processors with a TDP of 165 watts or greater should be paired with the high-performance heatsinks. Each heatsink also has a black plastic retention clip on its underside. This clip holds the processor against the heatsink and helps maintain the correct alignment during installation. The retention clip is a required part of the heatsink assembly and should not be removed.

Click to see standard-performance heatsinks

Click to see high-performance heatsinks

The final major cooling component is the air shroud. The shroud sits over the motherboard and directs airflow from the fans across the processors, memory, and other critical components. Without the shroud in place, airflow can be disrupted and the server may not cool its internal components as intended.

The fans, heatsinks, and air shroud should all be considered essential components of the R640 cooling system. Verify that all three are present and properly installed before attempting to operate the server.

Risers

The R640 10-bay configuration uses the same basic PCIe riser architecture as the 8-bay model. The most common setup consists of two risers providing three half-height, low-profile PCIe slots.

Riser 1 provides two low-profile x16 slots, both of which are connected to CPU1. Riser 2 is associated with CPU2 and provides an additional x16 slot. Because the PCIe lanes for Riser 2 are provided by the second processor, this riser will not function unless CPU2 is installed.

There is also a less common configuration that provides two full-height PCIe slots. These are also x16 slots, although the three-slot low-profile configuration is encountered more frequently.

If the server has the available risers, it is generally a good idea to install them even if you do not currently need every PCIe slot. Having the risers installed gives you additional expansion options if you decide to add a network adapter, HBA, storage controller, or other PCIe device later.

Click to see NVME configuration guide

NVME Configuration

The Dell PowerEdge R640 10 Bay supports NVME storage with the addition of some specialized cabling and an NVME controller. This is one of the major advantages of the 10 Bay chassis over the 8 Bay configuration. With the appropriate hardware, the system can be configured for 2, 4, 8, or all 10 front NVME drive bays.

There are three different Dell cable assemblies used to enable NVME connectivity in the 10 Bay chassis. We’ll start with the cable responsible for connecting the first two NVME bays.

DELL P/N 0M026C

This cable is essentially a Slim SAS cable that connects the NVME backplane to a dedicated NVME controller or expander card. Unlike the other NVME cables used in this configuration, this cable requires a separate controller card.

With the server facing you from the front, locate the connector on the lower-left side of the backplane. One end of the cable is labeled BP, which stands for backplane. Connect the BP end of the cable to the backplane.

There will likely be several other cables in this area that are in the way. You do not necessarily need to disconnect them, although temporarily moving them aside can make the installation easier.

The other end of the cable is labeled CTRL. Route this end alongside the backplane and then up the right side of the chassis.

Route the cable alongside the fans and then up the right side of the chassis.

Once the cable has been routed into position, you can install the NVME controller card.

DELL P/N 0CDC7W

Install the controller card into Riser 1 and connect the cable to the first port on the card.

At this point, the first two drive bays are enabled for NVME. If you only need two NVME drives, you can stop here. No additional cabling is required. Install the drives and the server is ready to use them.

If you want to enable additional bays, two more cable assemblies are required. Each of these cable sets provides NVME connectivity for four additional drive bays.

The cables labeled A0 and B0 provide connectivity for bays 6 through 9. The cables labeled A1 and B1 provide connectivity for bays 2 through 5. The cable we installed above provides connectivity for bays 0 and 1.

These cables can be somewhat difficult to install if you have never worked with this chassis before. There is very little room to work with and getting everything routed neatly takes some patience.

Here is the next cable assembly:

DELL P/N 0684MR

Move to the right side of the backplane where the remaining Slim SAS connectors are located.

The connectors on this cable are labeled A0 and B0. Connect each one to the matching A0 and B0 ports on the backplane.

These cables then need to be routed all the way toward the left side of the chassis. Follow the cable channel and route them toward the Slim SAS connectors located at the rear-left side of the motherboard.

Now we can install the second cable assembly, which is labeled A1 and B1.

DELL P/N 0TXC4H

Do your best to keep these cables tucked neatly into the chassis. Alongside the fans there are several hooks designed to hold the cables in place and prevent them from moving around.

When routing the cables through the left-side channel, I recommend temporarily pulling the existing cables out of the channel. You do not have to disconnect them. Simply moving them out of the way makes it much easier to route the NVME cables through the channel.

Pull the existing cables out of the side channel temporarily to make routing the NVME cables easier.

Once the cables are routed into position, you will see the corresponding connectors at the rear of the motherboard.

Locate the connectors labeled M1, M2, M3, and M4 and match the cables to their corresponding connectors.

Once all three cable assemblies have been installed, the R640 10 Bay will have NVME connectivity for all 10 front drive bays.

You do not have to install all three cable assemblies if you do not need all 10 bays. The NVME configuration can be built incrementally depending on how many drives you intend to use. If you only need a portion of the chassis configured for NVME, install only the cable assemblies required for those bays.

With all three cable assemblies installed, the R640 10 Bay is fully configured to support 10 NVME drives.

Building the Server

Once you have verified that the chassis contains the required components, you can begin assembling the server. Before installing every component, you can perform an initial power-on test using only the hardware required for the system to POST.

At a minimum, you will need:

• At least one CPU
• Memory
• At least one power supply

Required Tools

Fortunately, assembling an R640 does not require a large collection of tools. The basic tools and supplies you should have on hand are a Phillips #2 screwdriver, a T30 Torx bit, thermal paste, and either an electric air blower or a can of compressed air.

Keep in mind that a single-CPU configuration will disable some of the server’s hardware. Depending on the configuration, certain PCIe slots and even entire risers may be unavailable when CPU2 is not installed.

Installing the Processors

The two processor sockets are located near the center of the motherboard and are labeled CPU1 and CPU2. Depending on how the server was previously configured, the sockets may be covered by heatsinks or protective CPU socket covers.

Before installing a processor, remove the existing heatsink or socket cover. The blue retention clips must be released to remove these components. These clips can become brittle after years of exposure to heat, so do not be surprised if one breaks during removal. Replacement clips are available, although they are not strictly required for the server to operate.

With the socket exposed, take the opportunity to inspect the CPU pins carefully. Use compressed air to remove dust and debris, then examine the entire socket for bent, damaged, or crushed pins. The pins are extremely delicate, and even a small amount of damage can cause problems with memory channels, PCIe devices, or other portions of the system.

Once the socket has been inspected and the pins appear to be in good condition, the processor can be installed.

There are two common approaches to installing the CPU and heatsink. Some people attach the processor to the heatsink first and then install the assembly into the socket. Others, myself included, prefer to place the CPU directly into the socket and then install the heatsink on top.

For older R640 systems, I prefer the second method because the plastic retention clips on the heatsinks can become fragile with age. A processor that is not securely retained by the heatsink can fall out while the assembly is being positioned, potentially damaging the CPU socket pins.

Regardless of which method you choose, pay very close attention to the orientation of the processor. The gold alignment triangle on the CPU must correspond with the orientation marking on the motherboard socket.

Never force a processor into the socket. Installing the CPU in the wrong orientation can damage both the processor and the delicate socket pins.

After the CPU is correctly positioned, apply an appropriate amount of thermal paste to the processor. You want enough paste to provide full coverage between the CPU and heatsink without applying an excessive amount.

Position the heatsink over the processor, making sure the black plastic retention clip is installed correctly, and then secure the heatsink using a T30 bit.

If you are installing a second processor, repeat the same procedure for CPU2.

Installing the Memory

The R640 has six memory channels per processor, with two DIMM positions available per channel. This gives each CPU access to 12 DIMM slots, or 24 slots total in a dual-processor system.

The easiest way to populate the memory is to start with the primary DIMM in each channel. On the R640, these are the white DIMM slots. Once the primary slots have been populated, the secondary black slots can be used.

Ideally, memory should be distributed across as many channels as possible rather than filling both DIMMs in a single channel before using the remaining channels. When running two processors, the memory configuration should also be balanced between CPU1 and CPU2.

For example, if you have eight identical DIMMs to install in a dual-CPU system, a balanced configuration would be A1 through A4 on CPU1 and B1 through B4 on CPU2.

Click here to view the R640 memory channel mapping

CPU (Socket)	Memory Channel	Primary DIMM (1 DPC)	Secondary DIMM (2 DPC)
Socket 01 (CPU1)	Channel 0	A1	A7
	Channel 1	A2	A8
	Channel 2	A3	A9
	Channel 3	A4	A10
	Channel 4	A5	A11
	Channel 5	A6	A12
Socket 02 (CPU2)	Channel 0	B1	B7
	Channel 1	B2	B8
	Channel 2	B3	B9
	Channel 3	B4	B10
	Channel 4	B5	B11
	Channel 5	B6	B12

If you are starting with a single DIMM, install it in A1.

For a dual-processor configuration, install the matching DIMM in B1.

Continue adding DIMMs according to the recommended population sequence, keeping the memory configuration balanced between the two processors whenever possible.

Installing a RAID Controller

The next step is to connect the drive backplane to a storage controller. The R640 can use the motherboard’s onboard SATA controller, but that configuration is limited to SATA storage. If you want to use SAS drives or take advantage of hardware RAID, you will need an appropriate PERC or HBA controller.

For this build, we will be installing an H730P Mini Mono controller.

Before installing the controller, make sure you have the correct PERC cable identified earlier in the guide. The backplane has two Mini-SAS HD connectors. The cable connects to these ports and is routed along the right side of the chassis before terminating at the Mini Mono controller location.

Position the controller in the slot, sliding the edge of the card underneath the black plastic retention clips.

Once the controller is seated, secure the PERC cable to the controller using a Phillips #2 screwdriver.

Installing the NDC

The Network Daughter Card, or NDC, provides the R640 with its primary onboard network interfaces. Installing it requires temporarily removing Riser 2 and the small black plastic cover that protects the NDC installation area.

Align the NDC so that its network ports line up with the opening in the rear of the chassis. Once the card is correctly positioned, press it down firmly until the connector on the bottom of the NDC seats into the corresponding connector on the motherboard.

Secure the NDC using a Phillips #2 screwdriver.

Once the NDC is installed, reinstall Riser 2 and the black plastic cover.

Installing the Power Supplies

The final major components to install are the power supplies. The PSUs are installed from the rear of the chassis and slide directly into their respective bays.

Push each power supply firmly into its bay until the locking mechanism engages and the PSU clicks into place.

At this point, the major components required to start the server have been installed. The R640 is now ready for its initial power-on test and, assuming the required hardware is present, should be ready to begin POST.

The Dell PowerEdge R640 8 bay is a 1U chassis outfitted with 8 SFF SAS/Sata drive bays. The platform supports both generation 1 and generation 2 Intel Xeon Scalable processors as well as DDR4 ECC RDIMMs and LRDIMMs. This particular chassis has rather simple configuration options compared to its 10 bay older brother, which supports u.2 NVME drives. The 8 bay chassis has no support for NVME in the front drive bays due to no built in connections on the backplane.

In the rear the most common configuration is 3 half height expansion slots supported by risers 1 and 2 but Dell did make a chassis with 2 full height slots. Both of these configurations require different risers.

Essential components

If you’re building this server from the ground up you should first verify a few critical components required. These guides are written for someone who has a chassis in front of them, needs to get the chassis operational, but has almost no clue what he’s looking at or what is required to boot a functional environment.

Motherboard

The chassis should obviously have the motherboard screwed in. This is the primary hub where everything else feeds in. The power supplies will connect to the board from the rear, Both processors and memory will be installed on the board, the risers connect into the appropriate slots, the backplane will be wired up so you can stick drives through the front, and of course the hot swap fans will go straight into the motherboard. Verify the board is in the husk of the chassis.

Backplane and required cables

The second perhaps not so obvious piece of hardware is the backplane and the 2 required cables needed to connect the backplane to the motherboard. In most cases, any backplane (this includes rear flex bay backplanes as well) will have 3 required cables. The first cable is a signal cable, the second cable is a power cable, and the third cable will be a SAS PERC cable used to connect the backplane to a RAID/HBA controller. With this particular chassis you will most likely be using one of Dells PERC cables to attach a mini mono RAID/HBA controller. Take a look at the backplane and ensure all 3 cables are present. Without all 3 you will not have the ability to configure any kind of storage arrays.

Click to see picture of backplane

Click to see picture of signal cable

Click to see picture of power cable

Click to see picture of PERC cable

Cooling

There are a number of critical components the server needs for proper cooling and thermal regulation.

The first main component is of course the fans identified by the orange highlights. In general, the color orange indicates that a particular component is able to be hot swapped.

These are partially slotted in to fixed positions on the server chassis and then connect to the motherboard through a set of pins. There are 2 variations of fans – standard performance and high performance. Certain configurations may require high performance fans. If you’re using a CPU with a TDP higher than 165 watts they come recommended. Otherwise, standard performance will work. Either way you want to make sure the server has all 8 fans installed otherwise the server will not only complain and generate logs but you may run into serious thermal issues.

Another component critical for cooling is the heatsink. You will need 2 of these if you have 2 processors. These also come in standard and high performance variations. Standard is all aluminum. High performance have a copper face that draws more heat away from the CPU. Any processor >=165 watts should use high performance heatsinks. On the bottom of the heatsink is a black plastic clip. The purpose of these clips are to retain the CPU onto the heatsink and ensure proper alignment with the CPU pins. These are necessary.

Click to see standard performance heatsinks

Click to see high performance heatsinks

The last component related to cooling is the airshroud. The airshroud directs the cool air coming in from the server to critical components.

Both the fans, heatsinks, and air shroud are considered critical components to ensure proper operation of the server.

Risers

Both the R640 8 and 10 bay models use the same risers to provide PCIe connectivity to the system. The most common configuration is the 3 half height slot setup. This configuration has 2 risers. Riser 1 provides two low profile x16 half height slots. Both these slots are linked to CPU1. Riser 2 is linked to the second processor and provides a single x16 slot to the system. Riser 2 will not function without the presence of CPU2.

As mentioned there is also a chassis that has 2 full height slots. These are also x16 slots although this configuration is less common than the 3 slot low profile chassis. It is a good idea to have all available risers installed. Even if you don’t need them now you may need them in the future.

Building the server

You can test the server by installing the minimum amount of components required to boot. To boot you will need at least one of the following:

• CPU
• Memory
• Power supply

Required tools

Not many tools are needed for this job. You will at the bare minimum need a Phillips head #2. A torque bit #30, some thermal paste, and electric air blower or can of compressed air.

Once again please note that in single CPU server configurations some components may be disabled – for example some slots or even entire risers could be rendered unusable.

Installing the processors

You will notice the slots for the CPU near the center of the chassis. They might be covered by the heatsinks or they could have a dummy CPU cover installed. The sockets will be labeled CPU1 and CPU2. Remove the heatsink or the cover prior to installing the CPU. Removal of the heatsink will reveal the CPU pins. You will have to depress the blue clips to remove the heatsinks and/or the CPU dummy cover. Don’t be alarmed if the clips break – this is common and unavoidable. You can replace them but its not entirely necessary.

Now is the time to do a proper visual inspection of the CPU pins. Start by grabbing a can of compressed air and blow out any debris and dust. Look closely at the pins. They should not be bent or smashed in. Bent pins can cause a host of issues with memory and other aspects of the server like PCIe devices.

If you’ve determined the pins are in good condition you can now place the CPUs into the socket. Some people like to first snap the CPU into the heatsink prior to installing. I like to place the CPU into the socket by hand and then snap the heatsink on top of it. Do whatever is most comfortable for you. The reason I don’t always install the CPU into the heatsink is the fragility of the retention clips. At this point these servers are getting quite old and the plastic doesn’t always secure the CPU. I’ve had processors fall out of the heatsink as I flipped them down to install into the socket, and I’ve damaged pins as a result.

The most important part of this step is aligning the gold arrow on the CPU with the orientation arrow on the motherboard. Installing the CPU backwards can damage both the pins and the CPU if enough force is applied.

Apply thermal paste in an amount that will spread evenly across the entire face of the processor. Screw down the heatsink with a T30 bit.

If you have a second CPU go ahead and populate the socket using the same method.

Installing the memory

Next, the memory can be installed. For the R640 platform there are 6 channels per CPU with each channel supporting 2 DIMMs each. This means for each processor there are a total of 12 DIMMs. I will include a channel mapping table below but you don’t really need it – simply populate the white DIMMs first and if you run out of those start populating the black DIMMs. Each white DIMM is a different channel and it’s recommended to spread memory across as many channels as you can. However you populate the DIMMs on one processor you should mirror the configuration on the other.

Let’s say you have a total of 8 sticks you want to spread across both processors. The recommended configuration would be to populate DIMMs A1,A2,A3,A4 and then DIMMs B1,B2,B3,B4 on the second processor.

Click here to see R640 memory channel mapping table

CPU (Socket)	Memory Channel	Primary DIMM (1 DPC)	Secondary DIMM (2 DPC)
Socket 01 (CPU1)	Channel 0	A1	A7
	Channel 1	A2	A8
	Channel 2	A3	A9
	Channel 3	A4	A10
	Channel 4	A5	A11
	Channel 5	A6	A12
Socket 02 (CPU2)	Channel 0	B1	B7
	Channel 1	B2	B8
	Channel 2	B3	B9
	Channel 3	B4	B10
	Channel 4	B5	B11
	Channel 5	B6	B12

Now install the DIMM into the primary DIMM of the first channel (A1)

Now mirror the configuration for the second CPU (B1):

If you have more memory continue to populate the DIMMs in the order suggested above.

Installing a RAID controller

In order for drives to be exposed on the system you will need to wire the backplane to a RAID or HBA controller. You can wire the backplane directly to the motherboards onboard controller but this will only expose Sata drives. If you want to use both SAS and Sata drives you will need to install a controller. In this guide we will install an H730P mini mono controller.

First make sure you have the cable mentioned at the beginning of this guide. There are 2 mini SAS HD ports on the backplane. The cable will plug into these ports and be routed along the right side of the chassis where it terminates at the mini mono slot below:

Place the controller in the slot by sliding edge of the controller under the black plastic retention clips:

finally, screw down PERC cable with a phillips head #2:

Installing the NDC

Now it’s time to install the NDC (network daughter card.) To achieve this you must first remove riser 2 as well as the black plastic cover shown in the photo below:

At this point reinstall both riser 2 and the black plastic cover.

Installing the power supplies

The last component to install are the power supplies. They slide in from the rear of the chassis.

The server is now ready to be powered up.

Compatible parts

For a complete list of compatible parts for this server please read the following post.