I have the MSI P67A GD65, i2500k @ 4.5g, 1.3v, sitting in a Coolermaster Elite 430 and cooled by the Corsair H50.
When the temps are reasonable, it gets into the early/mid 60's under Prime95, which is pretty decent in my book.
When the temps went up at the weekend, the temps shot up to the early 70's, so I presume if we hit 30 during the Summer, it will hit late 70's/early 80's, meaning I'd have to reduce the overclock, which I don't want to do really.
I am thinking of selling the H50 and going to a Silver Arrow, but I need to make sure this beast will fit the board, clearing the SFC module and fitting the case ok. My Corsair XMS3 ram should be fine.
Just in case anyone is interested, the mobo was no problem with the Silver Arrow, but the smallish Elite 430 cause a big problem, with the top exhaust fans having to be removed to fit it, so I'm returning the SA and sticking with the H50 for now.
After a fair bit of hassle, I managed to get the Silver Arrow in the case, although if it was 1mm bigger, I couldn't have attached the side panel and the fan is resting on the ram. The top exhaust fans had to go though.
After 10 runs of Intel Burn Test, which seems to run hotter than Prime95 for me, the max temp, with room temp of 19.5c, was 58c on two cores and the other two at 51c and 52c, so a good improvement and I'm glad I gave it another go. I'm using IC Diamond 24-Carat, so I'm not sure if that needs some burning in, in which case, the temps may go down further.
Even in the rare event of the UK hitting 30c, I can't see the cpu hitting 70c, so it looks like I'm sorted at long last. Now to sell the H50.