AMD Ryzen 9 3900X Power Usage Is Running Measurably Higher On Linux Than Windows

[bezirg]

I think these power-usage graphs must only be interpreted together with the perfomance graphs of 3900x for Linux vs Windows: https://www.phoronix.com/scan.php?pa...0-ubuntu&num=7 . Since AMD 3900x (and any high-core CPU) performs on average better on Linux versus Windows, it just may be the case that windows do not push the CPU to its capabilities, and instead idling/throttling on lower wattages.

[mumar1]

There is a lot of strange things going on with Ryzen 3000 under Linux, my 3900X needs 41 s for c-ray on Ubuntu 19.10 and 52 s on Ubuntu 18.04.3 both with kernel 5.3.0 rc6

[lucasbekker]

It's always the same story with new hardware and Linux. You should avoid buying the former or don't use the latter at least for half a year before all the bugs are ironed out.

It depends, most Intel hardware (and NVIDIA it you don't mind the binary driver) has good launch day support and performance on linux. AMD CPU's tend to be less trouble free in the beginning...

[LeJimster]

Agree with what birdie is saying, but its disappointing seeing Linux not being as power efficient at this stage considering it's used in servers. Makes me wonder if this is just exclusive to Ryzen 3000 or if Epyc is affected aswell.

I'm using a 1700 and even after all this time and different tweaks I found I was still effected by the c-state bug (i thought it was fixed for awhile), which means I can't take advantage of Ryzen's low power idle state. I hope things eventually get fixed, but I think you are right.. Better to wait a little while for any new hardware on Linux unless you like beta testing.

[birdie]

It's always the same story with new hardware and Linux. You should avoid buying the former or don't use the latter at least for half a year before all the bugs are ironed out.

Right now I have a Ryzen 3000 system and

• I can't get CPU temperature in Linux by default (I manually patched kernel 5.2 to get the k10temp driver working - how many users will do that?)
• lm-sensors doesn't see any sensors on my motherboard (there are two HW monitoring chips: one is detected but doesn't work, the other one is not supported at all)
• CPU temperature is a lot higher than in Linux (I'm talking about idle mode)
• Multicore CPU performance is quite lower than in Windows

And even in Windows 10 Ryzen 3000 is far from what I'd call stable and feature-complete.

[rene]

thats and interesting find. Hope some AMD guru meditation pin points the power saving register bit to allow some silicon to NAP more when idle, ..! ;-)

[phoronix]

Phoronix: AMD Ryzen 9 3900X Power Usage Is Running Measurably Higher On Linux Than Windows

Frequently brought up following our various Ryzen 3000 "Zen 2" benchmarks like the Ryzen 9 3900X vs. Core i9 9900K gaming benchmarks is how the Ryzen 9 3900X is pulling considerably more power than the similarly equipped Intel Core i9 system and those numbers are higher than what is often cited by Windows reviewers as the difference. I've begun investigating that power difference and indeed quite quickly could see Linux power usage being higher than Windows 10...

http://www.phoronix.com/scan.php?page=news_item&px=Ryzen-3900X-Power-Windows-Linux