cooling RTX 3090 Trinity OC – Hotspot Delta >50 °C after applying KryoSheet and new VRM pads

[jakob56]

Hi everyone,

I'm currently having a thermal issue with my ZOTAC RTX 3090 Trinity OC after replacing the stock thermal interface materials.

What I did:

•     Replaced the GPU thermal interface with a Thermal Grizzly KryoSheet
•     Replaced the VRM thermal pads (correct thickness, light but proper contact)
•     Reinstalled the cooler using a cross-tightening pattern and even pressure

 

The issue:

•     At ~280 W power draw, the GPU core stays at ~60 °C
•     But the hotspot reaches ~105 °C
•     This gives a hotspot delta of 45–55 °C, triggering thermal throttling

 

Additional notes:

•     No system crashes or black screens, just early thermal limiting
•     Mounting looks correct, and VRM pad contact seems fine

 

Any ideas or suggestions on how to reduce the hotspot temperature or improve thermal performance in this situation?

Thanks in advance for any help!

[PDifolco]

What happens at full load, which is close to 400W with OC?

3090 is a hotbox but 50C delta seems abnormally high, there may be some problems with the pads or the mounting pressure

 

[jakob56]

1 minute ago, PDifolco said:

What happens at full load, which is close to 400W with OC?

3090 is a hotbox but 50C delta seems abnormally high, there may be some problems with the pads or the mounting pressure

 

I actually can’t reach full load, because the card starts thermal throttling as soon as the hotspot hits 105 °C, which already happens at around 280W power draw. So pushing closer to 400W isn't even possible right now i think.

[GuiltySpark_]

Fortunately the problem is pretty obvious here. You’re going to have to redo it as something is clearly not right with your application. Possibly too thick on the thermal pads somewhere can cause this pretty easily. 

[WereCat]

A.) You don't have enough mounting pressure with the cooler

- not proper contact, check if you can tighten it a bit more

B.) Your cooler is mounted with badly distributed pressure

- make sure you tighten each screw around the GPU die as equally as possible with enough torque

[jakob56]

10 hours ago, WereCat said:

A.) You don't have enough mounting pressure with the cooler

- not proper contact, check if you can tighten it a bit more

B.) Your cooler is mounted with badly distributed pressure

- make sure you tighten each screw around the GPU die as equally as possible with enough torque

 

11 hours ago, GuiltySpark_ said:

Fortunately the problem is pretty obvious here. You’re going to have to redo it as something is clearly not right with your application. Possibly too thick on the thermal pads somewhere can cause this pretty easily. 

Thanks! I’ve already repositioned and re-mounted the cooler several times with even pressure and cross-tightening. The pads showed light contact marks, nothing excessive. 

 

Im out of ideas, maybe I just switch back to normal thermal paste..