CPU draws too much power in some games (schedutil bug)

[Amaan]

Some games like Hades, Doom, God of War (all verified) pull way too much CPU power, leading to extremely high temperatures and fan noise on both the LCD and OLED deck. You can minimize this by changing the CPU governor from schedutil to powersave but this only works optimally on lighter games. Hades will never need the full capabilities of the CPU, whereas something like God of War may *sometimes* need it. However, even in menus the CPU is pegged to max :(

Of course, you could also use a TDP limit, but you would effectively run into the issue of limiting to the TDP required by the most demanding scene in a game, so you still have very high power draw in menus/loading screens.

[Suguru]

I wonder if this is something that can be fixed by uninstalling PowerTools? Or even without it it still would draw too much.

I had to setup so many games, but will instead now change default mode from schedutil to powersave and test it out.

EDIT: Tested out powersave and it just flat out limits CPU clocks to 1700MHz, so it's better to keep schedutil and just limit CPU usage yourself to something around 2300MHz.

I tested 2300MHz and in most games it's that sweetspot that keeps the game 60/90FPS without putting CPU fan into turbospin mode.

[Amaan]

Regardless, I view this as treating the problem rather than finding a solution and would like to see Valve address the CPU weirdness.

[Suguru]

Well, what I posted was just a workaround, so I am as eager as you to see a permanent fix.

This reminded me of early problems with custom ROMs on Android phones, where power consumption was bigger and you had to fix it yourself, kek

[Rodomar705]

They are still using acpi_pstate for managing CPU frequencies, so I'm not that suprised that it's not perfect (it has like 4 different power states). AMD has a new CPU scheduler (amd_pstate), but it's broken on LCD and not enabled in SteamOS by default anyway, so I would not be surprised if that is also one of the causes of bad CPU scaling.

[Amaan]

Fascinating - I imagine this is a tough problem to solve and AMD may have to be involved. It would help the Deck so much. I mean, manually limiting the APU and I get like 7 hours of battery life at 90fps on Hades. Reviewers only get like 60% of that. And those reviews stay on the web forever!

[Rodomar705]

Originally posted by Amaan:

Fascinating - I imagine this is a tough problem to solve and AMD may have to be involved. It would help the Deck so much. I mean, manually limiting the APU and I get like 7 hours of battery life at 90fps on Hades. Reviewers only get like 60% of that. And those reviews stay on the web forever!

Feel free to add your feedback on this here https://github.com/ValveSoftware/SteamOS/issues/1243