My current machines(s) don't show any symptoms with GPUgrid, other than a little more local warming.

I did have a ancient Pentium box which hiccuped its way through everything if the GPU was in use, and of course, if you're running intensive apps anyway then GPU availability might be staccato.

I think the only advice for others is to try it and see. I have a lowly desktop box with a G3258 ($50) dual-core and el cheapo GT640 which seems unstoppable, even at 100 per cent WCG and CPUgrid.

There are no discernible problems on my i7-2600K at 100% other than it operates as a room heater.

But I don't run GPUgrid on my creaking i3 laptop. :-)