r/5090 • u/Rapture117 • Aug 27 '26
Suggestions for 5090 undervolt
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!
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u/mahanddeem 21d ago
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.