Very poor performance in RAM test results with Passmark on Dell 7920 tower workstation.

This message is similar to another at

https://www.dell.com/community/Precision-Fixed-Workstations/T7910-memory-passmark-very-low/td-p/7778630

but there are sufficient differences to make it worth creating a new post, as they are different computers (7910 vs 7920), using a different type of CPU.

I have a Dell 7920 tower workstation, with Windows 10 build 19042 (64-bit). I run the Passmark performance test software

https://www.passmark.com/products/performancetest/index.php

Version 10.1,  Build 1002, with some pretty depressing results on the RAM.

I have the following hardware in the workstation, which has been upgraded since shipped from Dell. 

* 2 x Intel Xeon Platinum 8167M 26-core, 2.0 GHz CPUs, which run the RAM at 2400 MHz. These CPUs have 6 memory channels. They have pretty poor single-threaded performance. They clock the RAM  at 2400 MHz, which is the same as the Silver 4110 CPU shipped with the machine. Better CPUs can do 2933 MHz.

* 12 x 32 GB RDIMMs (384 GB total), with each DIMM in the correct socket, so each CPU has 6 DIMMS, and all 6 memory channels on each active.  One RDIMM s a 2933 MHz Dell SNP8WKDYC/32G AA579531 2RX4 DDR4 PC4-2933Y. The other eleven are Kingston KTD-PE429/32G DDR4 2933 MHz ECC RDIMMs.

* Nvidia Quadro P2200 graphics card

* BIOS upgraded to the latest version less than a week ago.

* NVMe PC601 NVMe SK hy (256GB)  - as shipped from Dell.

I run the Passmark performance software, and the machine does okay on most things, with a Passmark of 4772.4, which is the 62nd percentile of those computers submitted to Passmark. In fact, the dual 26-core CPUs put it in the 99th percentile of the systems submitted to Passmark. However, the RAM performance is really poor, with a score of 1937, putting this at only the 24th percentile. That's pretty poor, considering this should be a very high-end workstation.

I've attached a few images. I think when I looked at the RAM in more data in more detail, which I unfortunately forgot to grab a screenshot of, it was the "Database Operations" that was particularly bad. I have no idea what that equates to. (I'm now booted into my usual Linux operating system).

I've also given the data I saved as a text file from Passmark. For some reason Dell will not let me update a text file, so I have put it inline.

PassMark(R) PerformanceTest 10.1 (http://www.passmark.com)
Results generated on: Sunday, July 4, 2021
Number of processes used for CPU Tests: 104

Benchmark Results

Test Name: This Computer
Integer Math (MOps./Sec.) : 224594.9 (99%)
Floating Point Math (MOps./Sec.) : 140381.0 (99%)
Prime Numbers (Million Primes/Sec.) : 308.6 (99%)
Extended Instructions (SSE) (Mill. Matrices/Sec.) : 76055.8 (99%)
Compression (KBytes/Sec.) : 987356.8 (99%)
Encryption (MBytes/Sec.) : 23639.4 (94%)
Physics (Frames/Sec.) : 4653.2 (99%)
Sorting (Thousand Strings/Sec.) : 134164.4 (99%)
CPU Single Threaded (MOps./Sec.) : 1461.3 (12%)
Cross-platform Mark (Composite average) : 150109.4 (99%)
Simple Vectors (Thousand Vectors/Sec.) : 4.7 (4%)
Fonts and Text (Ops./Sec.) : 171.6 (30%)
Windows Interface (Ops./Sec.) : 49.7 (58%)
Image Filters (Filters/Sec) : 1535.2 (58%)
Image Rendering (Thousand Images/Sec) : 145.9 (57%)
Direct 2D (Frames/Sec.) : 37.4 (40%)
PDF Rendering (Ops./Sec.) : 28.2 (12%)
Direct 2D - SVG (Frames/Sec.) : 39.4 (31%)
DirectX 9 (Frames/Sec.) : 133.8 (58%)
DirectX 10 (Frames/Sec.) : 92.0 (57%)
DirectX 11 (Frames/Sec.) : 161.8 (54%)
DirectX 12 (Frames/Sec.) : 23.2 (37%)
GPU Compute (Ops./Sec.) : 3565.4 (53%)
Database Operations (KOps./Sec.) : 649.5 (3%)
Memory Read Cached (MBytes/Sec.) : 17396.1 (15%)
Memory Read Uncached (MBytes/Sec.) : 9174.7 (13%)
Memory Write (MBytes/Sec.) : 8761.4 (41%)
Available RAM (Megabytes) : 382215.3 (99%)
Memory Latency (ns (lower is better)) : 56.9 (86%)
Memory Threaded (MBytes/Sec.) : 201878.3 (99%)
Disk Sequential Read (MBytes/Sec.) : 1319.5 (56%)
Disk Sequential Write (MBytes/Sec.) : 1085.4 (69%)
IOPS 32KQD20 (MBytes/Sec.) : 1063.2 (79%)
IOPS 4KQD1 (MBytes/Sec.) : 23.1 (28%)
CPU Mark (Composite average) : 44716.3 (99%)
2D Graphics Mark (Composite average) : 524.4 (48%)
Memory Mark (Composite average) : 1937.4 (24%)
Disk Mark (Composite average) : 12405.2 (63%)
3D Graphics Mark (Composite average) : 8032.1 (52%)
PassMark Rating (Composite average) : 4772.4 (62%)

Operating System: Windows 10 Pro for Workstations build 19042 (64-bit)
CPU Type: Intel Xeon Platinum 8167M @ 2.00GHz
Number of CPUs: 2
Cores per CPU: 26
Hyperthreading: Enabled
Motherboard: 028PX1
Memory: 383GB RAM
Videocard: NVIDIA Quadro P2200
Hard Drive: NVMe PC601 NVMe SK hy (256GB)
Hard Drive: ST4000NM0035-1V4107 (4TB)
Hard Drive: CT1000MX500SSD1 (1TB)

PS - if you look, you will find other posts from me about only being able to use 4 memory channels due to  a motherboard fault. I have since replaced the motherboard, so now all 6 memory channels are working on each CPU, so this problem is not related to not using all memory channels. These CPUs clock the RAM at 2400 MHz, which is less than the 2933 MHz that a better CPU would do, but I find it hard to believe that the slower clock speed can make such a huge problem.

RAM performance at 1937 is only 24th percentile. RAM is clocked at 2400 MHz52 cores give good CPU performance, dessspite single-threaded performance is poor.Passmark aaat 4772 is 62nd percentile, which is pretty depressing considering the cost of the Dell 79202D graphics performance is not great, but better than Nvidia Quadrom P620 card shipped by DellAgain, 3D graphics performance is not stunning, but better than P620 shipped by DellNVMe disk is okay. This is original.