Its not the cooler itself as i recently upgraded from a h75, this is what i though the problem was. I have a corsair 600t btw.
Oh! In that case, I think I would temporarily remove the pump from the CPU and disconnect its wiring. Then install the stock cooler and run the same prime95 test. See what the temps are with the stock cooler so we have a comparison.
Are you using the Corsair Link software to modify anything?