CPU-bottlenecked in games on a ThreadRipper?

FeijoaBoa · October 17, 2019

Hi folks, I think I built a really dumb/unbalanced PC and I'd love any advice on what I can do to nudge it towards sanity without rebuilding it entirely.

Main specs:

CPU: Threadripper 2990WX

GPU: 2080Ti ("ASUS ROG STRIX RTX 2080 Ti Advanced Edition")

RAM: 2x 16GB DDR4-3200 ("G Skill F4-3200C16-16GVK")

Disk: Samsung 970 EVO Plus 1TB

Disk: Random assortment of old SSDs and rust

Mobo: ASUS ROG STRIX X399-E GAMING

Power: Some ancient Antec 900W

Software: Windows 10 Pro 64-bit, build 1903

Bios: Latest version, 1002

Cooling: A Noctua heatsink with 2x 140mm fans (sorry Linus, I like the brown)

Is it a gaming PC? Is it a workstation? What dumb-ass thing is this? I just kinda want it all!

My issues with the build are related to gaming. It looks like I'm CPU bottlenecked in VR which is causing reprojected frames. And my PCMark scores are kinda low compared to "similar systems". (See attached images)

My hypothesis is that the low single-core performance of my CPU is bottlenecking me. I have several ideas on how to fix this without a rebuild:

Add 2 more sticks of ram, to go from dual-channel to quad-channel (it has 8 slots?! Is there such a thing as oct-channel?)
Overclock the CPU. I was able to run Cinebench at Level 2 "Performance Enhancer" but gaming was unstable. I followed this guide: https://www.youtube.com/watch?v=LD66CSR8mnU - I possibly need:
- More power/bigger power supply
- Better cooling. Temps didn't look too bad, but cinebench ran too quick to get a good test and prime95 always made windows too slow to use so I couldn't check temps.

Things I already tried:

Latest version of windows, to ensure that the numa-node assignment issue is fixed
Latest BIOS

So my questions for you fine folks are:

Do you think I'm right about the CPU bottlenecking, or could there be something else causing the slowness in VR? Will more memory channels help? Will overclocking help? For OC do I need a larger power supply? For OC should I get more cooling? Do you have any suggestions I've not thought of?

_{PS I'd love your recommendations on monitoring temps for OC. I did some digging, and ThreadRipper has some funny business with reporting temps (it reports die temp, and then some estimated "real temp" that is Tdie + 30 or something), and the only tool that gets the info correctly is HWInfo, which I can't get to produce nice graphs.}

xAcid9 · October 17, 2019

Did you select Game Mode in Ryzen Master software? That will disable half of the cores iinm.

WereCatf · October 17, 2019

3 minutes ago, FeijoaBoa said:

Add 2 more sticks of ram, to go from dual-channel to quad-channel (it has 8 slots?! Is there such a thing as oct-channel?)

That won't fix a CPU-bottleneck.

3 minutes ago, FeijoaBoa said:

Better cooling

That'll only help if the problem is overheating, which is unlikely.

5 minutes ago, FeijoaBoa said:

and the only tool that gets the info correctly is HWInfo, which I can't get to produce nice graphs.

You don't need graphs, you just simply need to know the max-temperature the CPU-cores hit. And guess what? HWinfo gives you that!

FeijoaBoa · October 17, 2019

34 minutes ago, xAcid9 said:

Did you select Game Mode in Ryzen Master software? That will disable half of the cores iinm.

Didn't even know about that software I'd been limited to messing in the BIOS all this time! And HOLY CRAP this made a huge increase to my 3dmark score, from 7170 to 11295?! Somehow even the CPU test improved?!? How is this possible? I just wish it didn't take a reboot to enable the 'Legacy Mode' that seems to be the thing that helps.

I really want to check if it improves Beat Saber, but I broke my ankle last week sooooo.....

49 minutes ago, WereCatf said:

That won't fix a CPU-bottleneck.

The internet agrees with you, but I hoped...

50 minutes ago, WereCatf said:

if the problem is overheating

Nah, it never gets above 80, so I think things are fine. And the 'Ryzen Master' software has really nice charts - I find them useful to see if the temp increases have levelled off and reached steady-state, then I know that testing has been sufficient.

I guess that just leaves me with whether overclocking is any use. Does anyone know the difference between 'Precision Boost Overdrive' (and good settings) vs the 'Performance Enhancer' my BIOS has? (are they the same?) and whether my power supply is enough.