CPU intensive, unless you're running a GPU client. If you want to increase speed, bring the bar up to the right and it will raise the priority; otherwise it is set to fold at the lowest priority.
I have now rigged up my HD4670 as my main video card and I have my GTX 260 dedicated to folding. Have them both in the same board, was really easy to setup too.
my client keeps on crashing when i don't use the computer for awhile i would just surf and i got off and when i got back on in the morning it crashed at 92% it crashed again today at 57% This time it actually saved what I had