At stock settings my rig draws about 500~520 W from the socket (dual X5680's and
one Titan folding).
Interestingly, BOINC (which I'll be running, F@H was just a test run for the time
being) only draws between 390 and 480 W. From what I can tell, BOINC's CUDA
projects (at least the ones I'm running, which are GPUGrid and Milkyway@Home)
do not push the Titan as hard as F@H's OpenCL code.