My computer has Windows XP / SP2. It runs for a while normally, then slows dramatically, to the point where it essentially stops. The duration of normal behavior can be minutes to hours, and has no obvious pattern. Windows Task Manager shows no obvious clues. I've followed the directions on the page "I'm infected - What do I do now?" - Ran Malwarebytes, professional edition (which I purchased last year, and which is updated frequently). Malwarebytes reported no issues. - Ran Avira AntiVir, which I also purchased last year. It reported no issues. - Ran DeFogger. DDS.txt and Attach.txt are uploaded. - Ran GMER Rootkit Scanner, several times, under different names, from a few separate downloads. Two types of behavior occurred. 1) The Blue Screen of Death crash dump. This shows DRIVER_IR1L_NOT_LESS_OR_EQUAL ... nvraid.sys - Address BA716E73 base at BA710000 2) The usual dramatic slowdown, but this time showing 100% CPU utilization, with explorer.exe hogging CPU time. The last time this occurred, I killed explorer.exe via Task Manager. My desktop disappeared, but GMER ran for tens of minutes, until the Blue Screen crash dump (above) appeared. During this time, avguard.exe, System, and lsass.exe were using enough CPU time to push CPU utilization high (80+%), but not enough to cripple GMER. I've uploaded Attach.txt (zipped) and DDS.txt (not zipped). There is no GMER log to upload, since GMER did not complete. I've also run CHKDSK and SFC /SCANNOW, and neither showed any problems. Any ideas? Thanks in advance! DDS.txt Attach.zip