[Note: I posted this in the AMD Game Forum as well, and posted the message to Catalyst Crew Driver Feedback].
With particular driver versions the OS clock slows down when particular application features are used.
We are a developer. Our application is written in .NET 3.5 (WPF) and uses the "DropShadowEffect" object. We noticed that the Windows clock was losing time before periodically resyncing. This is under Windows XP. I didn't have another box to test this on with Vista or Windows 7.
I created a test application that uses DropShadowEffect heavily and was able to see a slowdown of 2 seconds every 10 seconds. Test steps:
- Boot Windows XP. Don't run any of our other developed software to keep the test case simple.
- Open the Windows clock.
- Run TestDropShadowPerformance.exe.
- Start the stopwatch on my wrist at time X.
- At time X+10 seconds on the XP box, my watch reads ~X+12 seconds.
- At time X+1 minute on the XP box, my watch reads ~X+1:12.
We discovered that rolling back to version 8.591.0.0 or 8.561.0.0 appeared to resolve the problem. 8.681.0.0 is the driver we were using that had the problem.
We initially thought we had a bad board (VisionTek ATI Radeon HD 4670 1GB), but replaced it with an identical board from Best Buy and had the same problem. We also tried an XFX ATI Radeon HD 4850 1GB and observed the exact same behavior.
If you would like, I can provide the source code for the TestDropShadowPerformance.exe app or the binary. It is a very small application. It is Xaml + C#. I don't believe the Xaml will display if I use the Attach Code button, since it's essentially Xml, so I'm not bothering doing that at the moment.
We have a large client that is pushing very hard for us to contact ATI and find out your take on what's going on here. Therefore it is extremely important to me that I get in touch with someone, either over the phone or via email, as quickly as possible. Even if the only correspondence I get is "thank you for letting us know; we didn't know about this but we'll look into it", I believe that would satisfy the customer. If possible, please contact me as soon as possible about this.