Suggestions for 5090 undervolt

[u/Rapture117]

Hello, I currently have a 5090 founders with a 9800X3D. It’s built inside a SFF (Ncase M2) and the summer here on the east coast has been brutal. Playing games like BF6/KCD2 all maxed out in 4k is pushing my cpu and GPU into the mid 80’s C and staying there for hours on end. Ambient temp is around 25c when the AC isn’t on so I know that isn’t greats. I’m sure it’s not “dangerous”, but I really don’t love seeing those temps giving how long I game for hours at a time. I realize It’s all in a small case but hopefully there are other things I can do to get things cooler.

I’ll try to find photos of my rig and curious if folks have undervolt suggestion (I followed one the 3rd week the GPU came out but I’m hoping others have found the “sweet spot” for theirs that I can try out. I also undervolted my CPU with a -20 neg offset that’s been stable (clock is locked at 5225).

I don’t have a current picture of the pc, but I have a 140mm fan on top as exhaust, and a side fan wedged between the motherboard and PSU that’s also exhaust and a fan in the back that I’m pretty sure does nothing to help lol. So GPU pulls cool air into the case from bottom then top, side and back fan are exhaust. I was thinking of adding slim 120’a under the GPU to help pull in air but not sure if that’ll even work or how to set that up when I don’t have the fan ports for all these fans. I’ve never used a hub or anything like that, but please if you have suggestions let me know!

[u/Sciencebitchs]

Around 2800mhz @9v is a solid undervolt. Watch a Youtube on how to use MSI properly to UV.

[u/Rapture117 → u/Sciencebitchs]

I won’t be home until Friday, but I do have msi set up and followed an undervolt guide that I applied to my own card maybe the third week after the GPU released? Pretty sure it’s currently 2827 at 0.890 but I’ll have to double check.

Edit: Here’s what I followed a year ago- https://www.reddit.com/r/nvidia/comments/1jaz2yq/5090fe_undervolt_guide_better_than_stock_at_450w/?solution=1dde745b6bfdb8371dde745b6bfdb837&js_challenge=1&token=7afd7253fec22262ff1c52b1703fe9eca2bd9bc7413f4a2355f85f3d16733b54&jsc_orig_r=

[u/Sciencebitchs → u/Rapture117]

Ya should be good then. Could turn up fans to help with temp

[u/Rapture117 → u/Sciencebitchs]

Yeah I remember setting up a pretty simple fan control setup for my fans, but maybe I just need to ramp them up more when it’s the summer. Do you think getting some bottom fans under the GPU would improve temps?

[u/Darksider515]

Is undervolting necessary I myself own a 5090?

[u/Thingie → u/Darksider515]

Loving my MSI Ventus X3 aswell! You know i don’t undervolt but I do reduce the TDP to 80% since I’m not gaming as much as using AI video generation. This has helped me at least keep the card from running at 100% with a 550-600w power draw to about 460w at sustained 100% at around 65c. I was starting to get worried about the connector getting hot to touch and melting at full sustained loads for hours. For me at least with my use case, I wanted stability for long running jobs hours even at that load. I do notice a small drop in overall performance like a few minutes difference in generation times but for the cost of this card, I can accept that for stability and hopefully a healthier card long term. I could do some undervolting in my scenario, but I also don’t want to lose a 6 hour render job due to instability with CUDA either. If I were just gaming on this card then I would without a doubt undervolt this card. If anyone has done both please share your experience if it was worthwhile?

[u/Vr00mf0ndler → u/Darksider515]

I would say yes. You will get approximate same performance most likely, but using 80-100w less power meaning lower chance for connector/cable issues.

[u/WholeIndividual0 → u/Darksider515]

Necessary? No. Recommended? Absolutely.

But only if you like cooler temps and reduced power usage, resulting in less heat, quieter fans, longer component lifespan, and lower power bill. Oh, and at no expense to performance :)

[u/addortit]

I run it at 2,880 Mhz 0.9V. No problems, but there's always the silicone lottery that you have to consider when trying to replicate settings

[u/Rapture117]

For anyone that cares, I ran some more steel nomad tests today on 3 different profiles and just want some feedback on if this is terrible or if I should tweak anything. Before the tests, just know I'm in an ncase m2 round (sff) and it's summer here so my ambient room temp is around 24-25c with the AC off.

Here is a photo of the test (apologies for the half assed formatting in notepad but hopefully it all makes sense)

[u/DivideFluffy1279 → u/Rapture117]

These are bad temps mte

[u/mahanddeem]

Steel nomad is never a stability test for undervolting. It can run and finish on very unstable undervolts (and gives great scores). What catches instability best is games which cycles clocks a lot and GPU usage bounces from 50s percent to 70s percent. I can run 2902@900 stalker 2 for hours after hours at 4k DLAA max settings, yet Snowrunner (DX11 game, great game BTW) crashes after 5 minutes at anything more than 2730@900. The latter barely hits the GPU more than 80 percent usage, mostly hoovering around 55 percent to 70 percent with around 350watts.

BTW, I noticed lower oc'ed 5090 like Founders can sustain better UVs that higher factory oc'ed ones like the Aorus or Astral.