What to use to watch/switch GPU clock/speed...

[tomtomme]

radeon-profile

Maybe this is what you are searching?

https://github.com/marazmista/radeon-profile

[agd5f]

I was on 3.13.11. I just tried 3.17.0-RC4 and it indeed seems to have solved this issue, with idle memory clocks correctly shown as 1125 MHz when a second display is enabled (a standard Radeon HD7770 / Cape Verde).

A bit disappointing since I hoped for a while that GPU power consumption would be better under Linux than under Windows with this usage. I guess this shows at least that power management works correctly with the open source driver, however.

I'm not sure how you could improve the memory reclocking. Memory reclocking has to be done during the vblank period to avoid display glitches during the reclock. With multiple monitors, the vblank periods are not likely to line up so you can't really dynamically change the memory clock. Note that when the displays are turned off (dpms off), the driver switches a low memory clock.

[Solid State Brain]

Recent NVidia video cards have a much lower (almost the same as with a single display) idle power consumption under multiple display usage than AMD ones, so in principle it should be possible, somehow. Perhaps not with the current AMD GCN architecture.


(from http://www.techpowerup.com/reviews/S...l-X_OC/23.html)