Wild stab1: Do these trouble machines have an on-board video in addition to a Video card and if so is it disabled?

Wild stab 2: Have you tried a project outside WCG?.... Try e.g. PrimeGrid which is pure math, no graphics.... your machine might run hotter!

For CUDA software the acceleration must be enabled, so your suggestions just isn't possible but I appreciate you're trying to help.

The driver seems to be quite good actually, it works perfectly with our graphics software, CAD, and functions flawlessly with the F@H GPU2 CUDA DC client. I can't find any relevant issues on the NVidia support forum for this type of issue with CUDA drivers. I think perhaps you're blaming the driver for a faulty client/project.

If you have any specific information on driver versions for certain projects I'd be glad to try it. Otherwise I really can't implement a "guess" as these are productions systems.

I have tried the earlier 177.35, and current 177.84 driver versions.

Sekerob,

No on-board video.
These systems wil run a prime burnin or two F@H SMP without issue. CPU temps are about 55c under 100% load.

What graphics is this client running? I only see text and a chart in the Boinc window. I am a bit confused as to why the video driver have any impact if I'm not looking at any graphics. Am I missing something?

I have shutdown all projects but one, and am going to give it one more try.

Interesting how you only see The BOINC logo and chart. Where? Is this the Screensaver or is this when you select a running job in the Task window of BOINC and hitting the Graphics button in the left margin.

The graphics for all BOINC projects are OpenGL.

Running 80% CPU load is not a good idea during problem solution. 100%.

Did you install BOINC as Service (Protected) or Single or All User?

Whatever Prime burning does like Prime95, I'm sure the machine will pass that test. The BOINC project PrimeGrid is a good trial to test the client stability itself.

As for the Drivers I use NVidia myself and am still on 175.19 for Vista, some WHQL release. Downloaded that on 21-8-2008.

Not so, although I can understand why you jump to that conclusion.

Why am I so certain? Firstly, it simply isn't possible for mere software to lock up a computer. Only kernel mode drivers have that kind of access.

Secondly, the graphics card is doing all the drawing - it is quite busy, even if it isn't actually drawing 3D graphics. If you are using Aqua, then it is very busy, alpha blending, double buffering. Vista uses DirectX 10 for drawing. There doesn't need to be a direct link between BOINC and the graphics. A bug in the driver is all it takes - one that only shows up when BOINC is stressing the system.

Thirdly, we have seen this before: experienced users swear blind that there is nothing wrong with their hardware, nothing wrong with their drivers (and they have test results to prove it) only for them to solve the problem by upgrading their drivers or replacing hardware. In all the years of World Community Grid, the software has never directly caused a hang. Indirectly, of course, it happens - as in your case. Sometimes as a result of overheating, sometimes as a result of intensive memory access. Sometimes, we simply can't prove the cause.

Report this problem to nVidia, and hopefully they will include a fix in their next driver update.

6.3.xx should only be considered and limited to just running e.g. PS3Grid. It's very much Alpha software!