7800 XT power-limited despite GPU load
Playing Assassin’s Creed: Shadows, my 7800 XT will be pegged at 100% utilization but won’t draw more than 160-180W despite its TBP of around 260W. In contrast, my other system with a the new RX 9070 will pull its full 220W without issue, and performance is noticeably better as a result.
Based on some google-fu, it seems like this is an RDNA3 bug dating back around 2 years that “should” be resolved in newer kernels, yet it seems to persist on my rig. I went to desktop mode and ran “ujust update” so I should be on the latest stable Bazzite packages.
Has anyone encountered a fix for this? The resulting FPS drops are so intrusive that I’m debating playing the game on PS5 instead, or swapping my older RX 6800 back in.
Full System config:
Ryzen 7600X
Radeon RX 7800 XT
32GB DDR5
Gigabyte B650 ITX board
2TB Samsung 980 Pro
850W Corsair SF850 SFX
33 Replies
try using lact and see if you can increase the max tdp
ujust install-lactInstalled. Even after enabling the daemon and setting the GPU to max clocks (there doesn't seem to be an option for TDP), it's still not behaving as it should. According to LACT's historical graphs, it's barely pulling 100W.
Update. Same issue with the RDNA2 card, so it’s an AMD issue across the board. Awesome.
Also the power draw you get given by lact is different to what the AMD adrenaline software is reading
So your value will be look to be lower regardless
check your cables
it sounds like one is disconnected
then use the historical chart and check the throttling on the LACT program
Mine spikes up to 350watts to 160watts rapidly
(I botched my repaste)
Cables are seated, both of them.
and on the psu?
I even switched the 7800 to the 6800 and it’s doing a similar thing. 7800 won’t go above 180W, 6800 won’t go above 140W.
They’re clicked in solid. It’s a brand new PSU.
there is no throttling showing on the well
LACT is there?
what's the psu wattage range? 850watts?
yes.
yeah my psu somehow has 120watt rated cables for pcie input for some ungodly reason
or outputs of the psu
But I do reach 350 watts so that's not a problem
Anyway
Try swapping pcie ports for the psu-side
It’s the Corsair SF850. Same PSU that’s in my other PC, where the new 9070 pulls right up to its TDP without issue (also running Bazzite).
for a pcie port
you are on well
highests clocks/automatic as the preset right?
Yeah, that made no difference.
I'm not sure then what could be the case
I’m away from my PC now; swapping GPUs in an ITX build is a pain so I gave up for the day
swap the psu
I hope it isn't a faulty psu
well
if you want to
I can try different PCIE ports on the PSU next. But I didn’t have any of these issues when it was on Windows.
Yeah that's kinda how I feel
Which leads me to suspect it’s a Linux bug which is annoying because I don’t want to go back to Win11; Bazzite is perfect for the living room.
same but my zero-rpm function broke
on my gpu
but anyway yeah
it's etiher a hardware or software issue
I hope it isn't a cable issue either
I’ll mess with it again later; I’m out of patience for today.
Fair. But even in Gamescope it’s still showing about 100W below TDP, and the performance seems to reflect that.
What is the card manufacturer's set power draw?
100w is maybe a little bit more of a delta than what I'd expect, realistically I'd expect it closer to 75
Just as a reminder TDP != Power draw and isn't what LACT / AMD drivers as measuring
However, yes there is a bug with the drivers when talking about increasing power allowance above what is the default in the vbios
All of that makes sense. But something is definitely off, as a 7800 XT should not be less performant than a base PS5.
you dont have this slider? btw which model of 7800 xt you got?
Nope I didn’t see that at all.
Asus Dual OC 7800 XT
what is your output of
rpm-ostree kargsI’ll have to get back to you on that. Not home right now.
Also, will have to put the 7800 XT back in. I was under the impression it was a RDNA3 issue so I swapped the RX 6800 in
the kargs shouldnt be influenced by the gpu changes
When you do that, plz run the following (you may need to replace
hwmon4 with another number depending on your system.)
Hey, all, I decided to just move the 9070 to the living room PC (since that TV doesn’t have VRR and the GPU horsepower can help keep it locked at 60 fps), and I moved my 7800 XT to my office PC where the monitor has VRR. Going to mark this as resolved so as not to further bother the devs. I appreciate all of your time and input.
That said, it might be a PSU issue. The 9070 is no longer pulling 220W in this system, and even switched the PCIE ports used. Interesting.
Regardless, not a Bazzite issue.
The plot thickens!
I fired up Enshrouded, which is another GPU heavy title in my rotation, and it pulled 220W with zero issue or complaints. So it looks like this may be a driver/proton/game issue with AC: Shadows.
It is hard to say without knowing what the drivers think the power config should be
although annoyingly, AMD drivers have a long standing issue with power related settings that require a very specific order of operations to actually be registered
🙃 So even if you tell it to use X power allowance and the device files suggest so, it might just not