Information on Video Card Drivers

Just a FYI for some of you that may have recently developed issues with your DAW.

I just finished a build on a new Sandy Bridge system and ran into a problem while tuning and tweaking it for studio use.
 
As advised I updated my video driver for my nvidia 560Ti (along with all my other hardware), applied all the normal tweaks and ran dpc checker and was horrified to see a latency of around 3800 micro seconds.
After trouble shooting everything I could think of I started shaking my mouse rather violently back and forth while pondering my next move and the dpc dropped to 50 ms.

That set me on a hunt through nvidia's beta and archived drivers section and after rolling back 2 versions I now have a latency of 19-23 ms, and it's rock steady.
The link for dpc checker is here.

Nvidia has gone to a "unified" driver model and apparently they have some issues.

I don't know if this is just a sandy bridge issue or if it's all the 3d crap and HDMI audio drivers you get if you don't do an advanced install. Incidentally my new i7 sb laptop was over 5000 ms and I roll it back several versions and got it calmed down with a beta. One thing to look for is the screen activity (like angry mouse) actually lowering the latency and smoothing it out.

So if you have recently developed problems and you haven't made any changes that you know about, check your dpc and see if your video driver has auto updated recently and if you do need to test some older drivers make sure to do an advanced install so you can uncheck the nvidia updater and any audio or 3d components you don't need and check the box marked clean install. The nvidia beta and archive search page is here.

Hope this helps someone out.

Eric