Concerns about GPU throttling on XPS 1647 w/ Radeon 5730

Good morning, everyone!

So last night I was playing World of Warcraft in bed with a laptop tray (but w/ no fan). I noticed performance was a little choppy, so I pulled up good ol' GPU-Z to see if I was being throttled. Sure enough, it listed me as running at 550/800 rather than 650/800. Frustrated, I figured that maybe it was time to upgrade the video drivers... I won't go into that particular saga except to say that my benchmarking after upgrading to Catalyst 10.10 were disappointing.

For reference:
> My first run of 3DMark06 on a vanilla system, fresh from the unboxing ceremony clocked in just shy of 8100 (819x).
> After upgrading to Catalyst 10.10, 7900.
> I downgraded Mip-Map settings to "performance" and I'm back to 8050. All other options are set to "Application controlled."

I tried running GPU-Z during the benchmark, but apparently it stops logging while the benchmark runs. So I see a bunch of 100/150 entries followed by a gap of 15 minutes then 650/800 for a few seconds then back down to 100/150.

The 3DMark06 benchmark ended with the GPU at 100/150, at which point I decided to run FurMark's burn test. FurMark continued to read the GPU at 100/150, which never got any higher, the fan never kicked in. I ran FurMark after unboxing as well and I was able to peg the clocks and run at 77C for several minutes with no sign of throttling.

To make things more confusing... Right now, after many reboots (due to my Catalyst installation saga), everything kinda seems normal. I'm concerned that I may have taken a 3DMark06 hit with the driver upgrade, but at least FurMark is singing like it did at the unboxing.

I am SO confused on how the GPU throttling works and it's driving me nuts because in the end, I just want consistent performance out of my games. If I hit a patch of sub-30fps in World of Warcraft, I want to know that it's because the scene is simply difficult to render, not because the GPU or the BIOS decided to arbitrarily downclock my video!

Does anyone out there actually know how the throttling works and what I can expect? Why would it decide to kick me down to 550/800 playing World of Warcraft? How can I prevent it from doing so again given that I'm able to run FurMark for extended periods of time without throttling (7 minutes, 76C, full clocks as I speak now)?

Thanks much!
-Mox

 

Did your powercord fall out for a second? Running on battery will cause you to downclock slightly. Most examples I've heard of with GPU throttling, it will drop down to 300 or below, not just a small drop to 550.

On GPU-Z, check the 'continue to refresh while in background', and then run WOW. Check the logs when you suspect throttling, and look at clocks and temps. The GPU won't start throttling till around 84, and WOW shouldn't get a 5730 anywhere near that temperature. If it does, you may want to clean out your heatsink/fan in case it's full of dust or something.

 

Twice now it's "permanently" downclocked to 550MHz. Each time the circumstances were a little different and I'm not sure what's causing it. I've run a series of tests with FurMark to see if I could replicate it. Here's what I've found:

1. Unplugging the power downclocks immediately to 300MHz. When the power is reconnected, it clocks back up to 450MHz and then to 650MHz within 5-10 seconds.

2. Minimizing FurMark seems to have no effect.

3. Briefly unplugging it seems to have no effect (i.e., a powercord "oopsie").

4. Extended runs of FurMark have no effect, when when OC'd to 800MHz via the AMD tool. i.e., it doesn't seem to hit 84C, so it doesn't need to downclock.

5. Sitting idle at the desktop seems to engage a low power mode where it downclocks to 100/150.

6. Rebooting seems to fix the 550MHz downclock problem, as does running the AMD tool (obviously)

So...I'm still perplexed because I haven't been able to replicate the original symptoms. I haven't run an extended WoW session with GPU-Z running continuously. That will be my next test when I get the chance.

 

If you're letting it fall asleep or hibernate, that's what's causing it.