Response below... << Steve, I have an almost identical QS, including CPU upgrade. A couple things to consider here. . . KPs are generally caused by either 1) hardware incompatibility or fault, 2) bad kernel extension software, 3) overheating (see 1) If you haven't changed your hardware config lately, it could be overheating, especially since the dual 1.8 is an overclocked CPU to begin with. I had this problem with my GigaDesigns card (purchased early this year). The company replaced the card after asking me to do a voltage (jumper) change and some additional testing. In my case, I run the folding at home client software, which maxes out the CPU usage 24/7. I didn't see any problem with this card until the warmer weather appeared, and I wound up setting the card to 1.6 GHz to keep it stable. I eventually contacted the company with a description of the symptoms and they supplied me with a redesigned card, which has performed well and without problem at the rated 1.8 GHz. Do you run any processor-stressing software such as f at h? To explore this option further, you could try resetting the clock speed to 1.6, and see if the problem persists. If so, I'd start examining other possibilities, such as a bad RAM module. HTH, Rick >> What is folding at home? After I sent the e-mail about this, I imported the music with no problem. I left the computer on all night. (It doesn't sleep, probably cuz of the USB 2.0 card) Anyway, I think I'll wait to see if this happens again. So far the QS has been bulletproof since the Giga upgrade before summer, through about 35 cassette imports, until now, that is. The memory issue does give me pause, as I got conflicting reports from different ram testing programs I ram not long after I bought the machine. For now, I'll see if I have more episodes like last night, in the future.I assume that more will come if there is a real problem. STeve