ASUS RS720-E12-RS8G 2U Intel Xeon 6 Server Review

Credit: Patrick Kennedy - STH, source: www.servethehome.com

The ASUS RS720-E12-RS8G is a 2U server heavily influenced by open standards to create a flexible compute platform. The server supports up to 10 expansion card slots, eight PCIe and two OCP NIC 3.0 slots, eight front NVMe drive bays, and dual Intel Xeon 6 CPUs. There is a lot to get into, so let us get to the hardware.

For this one, we have a short that you can find here:

We are working quite a bit on our shorts channel this year and are trying to give folks 1-minute overviews of servers. This is also a review that Ada took photos and b-roll for, and she is a much better photographer than I am.

ASUS RS720-E12-RS8G External Hardware Overview

This is a 2U server at 32.7 inches or 830mm depth making it a fairly standard size. We also see a front that reminds us a lot of some of the other server designs we have seen recently.

On the left side, we get two USB ports, and then a vented area. In many of the modern 2U servers where GPUs are an option, the front has a few drive bays, then large openings for clean cool air.

In the center, we get 8x 2.5″ drive bays.

By default, these are wired as NVMe, but if you want to run SAS or SATA you can do that as well.

The trays are ASUS standard tool-less designs.

On the right side, we get another large airflow section with our power button and status LEDs.

Turning to the rear, we get perhaps one of this server’s most unique features, and that is a lot of I/O. There are a total of eight full-height riser slots as well as two OCP NIC 3.0 slots. This is an OCP DC-MHS style design that is using the M-FLW motherboard, so it makes this style of platform.

On the left side we get a 3.2kW PSU and a double riser.

In the center we get another double riser, two single risers, and then the rear I/O of a management port, two USB ports, and a mini DP port for video.

On the right center’s bottom row we also get our two OCP NIC 3.0 slots.
On the right side, we get another double riser and another 3.2kW PSU.

Here is one of the double risers. These allow for either two PCIe cards or a single double-width card like a GPU. The server itself supports up to three GPUs.

Here are the two lower single slot risers usually meant for networking.

Here is another shot of those risers. All are tool-less to pop out of the chassis which is nice.

Next, let us get inside the system to see how it is made.

ASUS RS720-E12-RS8G Internal Hardware Overview

We are going to start at the front of the system, and work our way to the back.

The backplane for the front eight NVMe bays is fed via MCIO connections that run under the fan partition.

The fan partition has six dual fan modules.

Each of these modules is hot swappable.

There is an airflow guide that keeps the bottom airflow for the CPUs, memory, and NICs, and then the top for the PCIe slots, which can be GPUs. That is why the airflow is bifurcated like this.

On the bottom, there is the dual Intel Xeon 6700 series setup. This system can take either Intel Xeon 6700E or Xeon 6700P series CPUs. That means one can optimize for up to 288 E-cores or instead optimize for P-cores.

The heatsinks are 1U designs even in the 2U chassis, so to get extra space, there is an array of heatpipes to the front sections of the heatsinks.

These front heatsinks in the center are raised so the MCIO cables carrying PCIe to the NVMe front bays can pass underneath. This is a really cool design.

In terms of memory, we get 32x DDR5 DIMM slots since the Xeon 6700 series is an eight channel design. With two DIMMs per channel we get 16 DIMMs per socket or 32 DIMMs total. With the Xeon 6700P series, these can be MCR DIMMs/ MRDIMMs.

Onboard, we have a M.2 slot underneath the rear riser section.

Here is another look at the risers installed.

Here is a quick look at the riser slots and the POST code display. ASUS has had these little POST code displays for years.

With he risers out, here is a look at the CPU heatsink from the rear of the chassis.

Here is a view from the center of the chassis with the metal posts that guide the risers in place.

On the bottom rear, there are two OCP NIC 3.0 slots with internal latches.

Here is the DC-SCM with the ASMB12-iKVM out-of-band management solution.

Next, let us get to the block diagram and topology.

ASUS RS720-E12-RS8G Block Diagram and Topology

Here is the block diagram for the system. We can see the relatively even distribution of the PCIe lanes and the NVMe drive bays on CPU1.

Taking a look at the rest configuration with two NVIDIA H100 NVL GPUs, two Intel Xeon 6740P CPUs, and 1TB of memory, here is the topology.

This is very similar to what we see on other 2U Intel Xeon 6 servers.

ASUS RS720-E12-RS8G Management

In this system, we have the ASMB12-iKVM running on an OCP DC-SCM form factor. That puts the ASPEED AST2600 BMC on a removable board at the rear of the chassis instead of on the motherboard.

We have looked at ASUS ASMB generations and ASUS uses the MegaRAC SP-X design that has features like HTML5 iKVM functionality. We are not going to go into it deeply here since this is fairly standard.

ASUS RS720-E12-RS8G Performance

For the CPUs, we had two Intel Xeon 6740P processors which are 48 core P-core CPUs from Intel.

With these, the big question is how do those coolers perform. Are the coolers able to keep these CPUs cool and therefore running at full clock speeds.

This is very close to our baseline reference system numbers, so it seems like the answer is that the server is doing a great job.
We also had two NVIDIA H100 NVL PCIe GPUs installed.

The NVIDIA H100 NVL is the HBM3 equipped PCIe GPU that NVIDIA is targeting at systems that want to run AI acceleration instead of running graphical related tasks. We again wanted to test the GPUs running in this system to see how they perform and if the cooling for the GPUs is effective.

As we can see here, the NVIDIA H100 NVL GPUs with their 400W TDP limits are performing as we would expect. That is important. Some 2U servers can run the higher-TDP PCIe GPUs, but only at lower power levels like 300W. Getting the full 400W GPUs cooled well here is great.
Next, let us get to the power consumption.

ASUS RS720-E12-RS8G Power Consumption

On the power side, we have two 3.2kW power supplies from Delta which is great for this configuration.

Unlike the Dell PowerEdge R770 and its dual 1.5kW PSUs that we recently reviewed, with these 3.2kW power supplies we get redundancy even with GPUs installed. With three high-end GPUs, and two high-end CPUs, the power needs of this platform can easily hit 2kW just for the CPUs and GPUs. Adding eight NVMe SSDs, 32 DDR5 DIMMs, four NICs, and the cooling, this class of system can get into that 3kW range which is really impressive. If you are replacing a server, even with three PCIe GPUs from five years ago, this system can use around twice as much power which is very impressive indeed.

STH Server Spider: ASUS RS720-E12-RS8G

In the second half of 2018, we introduced the STH Server Spider as a quick reference to where a server system’s aptitude lies. Our goal is to start giving a quick visual depiction of the types of parameters that a server is targeted at.

Overall, this system has a lot of flexibility. We have seen some other 2U servers that support only two double-width GPUs, but this one supports three. While that is not the densest AI server, it is still good for a general purpose 2U server. With the massive number of PCIe slots, one can have those three GPUs and still fit four high-speed NICs at the rear which is awesome.

Final Words

The ASUS RS720-E12-RS8G is a really neat design direction from ASUS. It incorporates many of the industry standard OCP-inspired design elements that make for a flexible and expandable server. With the ability to add up to ten expansion cards, 32 DIMMs, and either P-core or E-core Intel Xeon CPUs, there is plenty to like in a platform like this.

ASUS did a great job with the serviceability of this design. Reviewing this server and the Dell PowerEdge R770 in the same week, it is easy to say that this was very similar in terms of functionality, but I actually prefer servicing this machine. Or perhaps better to say as someone who has taken apart literally hundreds of servers from different vendors over the years, if I had to pick either the RS720-E12-RS8G or the R770 to replace a NIC that failed in under 1 minute, I would prefer to do it on the ASUS. That is saying a lot.

Overall, I really like the design direction of the ASUS RS720-E12-RS8G. We have used many ASUS servers over the years and this is certainly a step forward both in the design and the capability with so many customization angles.