I have a KT7A-R week 49 northbridge(the bad week so I hear). I run 24/7 @ 150FSB CL2. I've had it running stable up to 155FSB, but haven't tried higher. Since then I've lapped and aplied Arctic Silver to stock HSF. I believe I heard that 160FSB is about the max on the KT133A chip. I think tomorrow I'll see just how high I can get my FSB to go, and I'll post back with the results.