Question Why is my GPU power consumption dropping in-game?

wajjie

Commendable
Oct 20, 2020
40
0
1,530
I recently upgraded my GPU to an RX580 and kept having the same problem while playing games. The power consumption and utilization percentage keep dropping randomly and then everything goes back to normal for about 30 seconds. I tried to find out what could cause these problems, but couldn't really come to a conclusion. I've had a GT1030 previously and installed new drivers on the same day as I installed it on my PC. Here are my specs:
I3-9100F CPU
16GB DDR4 2400MHz Corsair Vengeance LPX RAM
RX580 4GB GPU
Corsair CV650 80+ Bronze PSU
I'm pretty sure there is little to no bottleneck and my PSU is still in good shape since it hasn't ever failed me since I got it. Any suggestions/ tips to resolve this problem?
 

InvalidError

Titan
Moderator
There are three main reasons for low GPU utilization:
1- the CPU isn't able to push frames to the GPU fast enough
2- the GPU is throttling
3- the GPU ran out of VRAM and spends most of its time twiddling its thumbs waiting for system memory

Check CPU and GPU temperatures. Since you likely nudge the CPU HSF while removing your old GPU and installing your new-to-you old RX580, I suspect that the CPU HSF got nudged loose and the CPU is periodically thermal-throttling.
 

wajjie

Commendable
Oct 20, 2020
40
0
1,530
There are three main reasons for low GPU utilization:
1- the CPU isn't able to push frames to the GPU fast enough
2- the GPU is throttling
3- the GPU ran out of VRAM and spends most of its time twiddling its thumbs waiting for system memory

Check CPU and GPU temperatures. Since you likely nudge the CPU HSF while removing your old GPU and installing your new-to-you old RX580, I suspect that the CPU HSF got nudged loose and the CPU is periodically thermal-throttling.
Both the CPU and GPU are at about 90-100% while playing and their temperatures are normal. It's just that the GPU power consumption drops to about 90W from 180-200ish and causes some lag that can get pretty annoying.
 

InvalidError

Titan
Moderator
Power consumption dropping isn't the cause, it is a symptom of something else. The only thing besides throttling that reduces the GPU's power consumption is lower workload.

If you are reaching 100% CPU utilization when the drops happen, then you are in a CPU bottleneck situation where the CPU cannot send new frames fast enough to keep the GPU busy. The CPU bottleneck scenario can happen long before the CPU hits 100%: you only need the most performance-critical thread in the whole game to hit 100% of its core utilization, which can hypothetically happen at as low as 25% overall CPU utilization on a 4C4T CPU.