GPU Throttling?

Texun

Platinum Member
Oct 21, 2001
2,058
1
81
Google didn't return anything useful under Graphics Card Throtling so here's my question......

Does anyone know if a mid to high end graphics card does any kind of throttling when not gaming? Since temps rise with heavy games it would seem so but I've never seen any data on it. I don't game much but I'm looking at the 3850 and 3870 for some of the newer games like Bioshock and CoD 4.
 

Ika

Lifer
Mar 22, 2006
14,264
3
81
Most cards have 2D and 3D clocks (some, if not all, have low-power 3D clocks). If you're not using Vista Aero, when you go to desktop or something the card will usually drop to 2D clocks. Vista Aero uses your graphics card's 3D mode, so I think it runs in 3D mode (or low-power 3D mode, not sure).

I've only had experience with nVidia cards, though; maybe ATI cards behave differently.
 

tigersty1e

Golden Member
Dec 13, 2004
1,963
0
76
Vista Aero keeps it on 2d clocks...

Why would you want to know if the card throttles on 2d clocks?

I think a card does throttle all the time even on 2d clocks.
 

Texun

Platinum Member
Oct 21, 2001
2,058
1
81
I'm not using Vista. Just curious to know if it throttled back while surfing
 

Martimus

Diamond Member
Apr 24, 2007
4,490
157
106
My 3850 throttles the shader clock speed down to 300MHz while in 2D mode, and uses whatever your overdrive setting is in 3D mode. It seems that the memory speed does not decrease at 2D mode, however.
 

taltamir

Lifer
Mar 21, 2004
13,576
6
76
I don't think the reason it takes less power and generates less heat is due to throttling...
AFAIK (and don't quote me on that) while there are no moving parts, segments of the CPU/GPU simply do not have power physically running through them unless they are being used... that is, when you are running a game or calculation more power goes through the processor as various components in it are accessed and perform calculations.
I would love to hear more about the subject as my assumption on it might very well be wrong.

There are methods of down clocking and throttling but as far as I know they aren't very common, yet. (isn't that what AMD power play is about to do? nvidia on the other hand is about to release hybrid power (they have AMD mobos, but no intel mobo, or drivers, or video cards that support it yet), where a motherboard comes with built in graphics and when you are not in a game the video card turns off and the motherboard's built in graphics is used instead. (should save 100-200watts per video card while not gaming)
 

Martimus

Diamond Member
Apr 24, 2007
4,490
157
106
The 3850 and 3870 both reduce the GPU clock when not in 3D mode. It is to reduce power consumption. It works in a way similar to speed step, or Cool and Quiet. At the moment, they are the only modern nVidia or ATI cards to do that, but I would expect all future ATI cards, and the next generation of nVidia cards to do the same.