Prime95 ran 12 hours and 45 minutes at 2.7GHz with no errors and it could have ran longer, but I stopped it so I think I can safely declare the chip 100% stable at 2.7GHz and I'll leave memtest86 running when I go to bed. I tried those reference drivers and I had the same issue that I had with the Soyo drivers. It will play the Windows startup/shutdown sounds (and play them very clearly) but won't play any other sound. All the drivers I've seen were Win98 SE and up, so I'm beginning to suspect the OS at this point. On a side note, I ripped a couple CDs and they ripped about 15x faster than on my old PII-350! The 350 ripped them in approx. "real time" while this system rips them at a rate of ~ 20 seconds per song!