I got 1.33 version from newegg.com AYHJA stepping(it is AYHJA 9), when it was cheaper than non-AYHJA ones . Anyway, on KT7a-R (refurbished from newegg, too) it wont go higher than 1.45 (10x145) without bumping the voltage, even than the Prime95 halts calculations, and states hardware failure(I have 300W no name powersupply, and lots of drives, so it could be PSU issue). But windows works fine , nothing crashed after hours of work, no lockups, temp is at 35C idle, 50C under heavy load. I'll just leave it there. So it is not a huge overclock, but good enough for me, good luck with your attempts.