I never used to have problems with blue screens but recently my WinXP Pro computer has begun to crash and blue-screen on me very often; I've had five crashes already today! What's odd is that I hadn't installed any new hardware or drivers when it started happening. I've been running some long video encodes overnight, but I'd done that before without any problem until now. I upgraded the mobo/cpu in this computer in April and it ran fine until November when the crashing began. System specs: - Asus A8V mobo with Via K8T800 Pro - 1GB (2 x 512) DDR400 RAM - Athlon XP 3000+ cpu - ATI Radeon 9600XT videocard - onboard audio (Realtek AC97) - Windows XP Professional SP2 (fully patched) - Boot drive is a partition on a 120GB Western Digital drive running as Master on the 1st IDE channel (a second 120GB WD drive is the slave on this channel) - 2nd IDE channel master and slave are a Lite-On DVD-ROM drive and a TDK CD-RW burner - On-board RAID controller running two SATA 320GB WD drives in RAID 1 (mirror) - Westell DSL modem A few pertinent facts: - The blue screen is often (but not always) an IRQL_NOT_LESS_OR_EQUAL 0x0A error. - I monitor the temperature and voltage with Asus Probe but it never shows the CPU temp rising more than 42 C even when it crashes, and the mobo temp never gets above 26 C. (And I've run the unit with the case open but that didn't help.) - Asus Probe usually shows the +12V voltage line as being around 11.6 and the +3.3 around 3.28, but it still displays "OK" for these. - I have installed the newest BIOS and the newest chipset, video and audio drivers (after cleaning out the old ones with DriverCleaner). - I have run two memory tests (memtest and Windows Memory Diagnostic) overnight each but found no errors. - I've examined the memory dumps with Windbg. Most often these point to avg7rsxp.sys (my anti-virus software) as the culprit, but I've read this could be misleading since the antivirus software may just be active when the crash happens. So I uninstalled AVG antivirus, and the dumps usually point to ntkrnlpa.exe, but sometimes to ati2mtag.sys, sr.sys or ntfs.sys. - I reinstalled Windows using the "Repair Installation" option, but it didn't help. - I've run chkdsk /r and found only minor problems (e.g., free space allocation) and no bad sectors. - Sometimes the blue screens have happened while I was running some long task (like encoding or defragging) but sometimes they've happened while I was running nothing at all. - I removed, cleaned and reseated the RAM modules in different slots, but it didn't help. This has been going on for weeks now and it makes the machine virtually useless since running long operations on it is hit-or-miss. My questions: - Could re-installing Windows from scratch help? (The Repair Installation I tried did not.) I'd really rather not re-install it (and all my apps) from scratch if I can avoid it. - Could the memory be bad even if memtest found no errors? Does that seem likely? I have no spare modules to test. I don't mind buying new memory, but I'd love to know if that's likely before I spend $100 on it for no good reason. - I am including with this post a zip file of the five minidumps from today. Can anyone tell anything more from them? A couple of other things: Coincidentally (I think) the optical drive I was using in this machine -- a Plextor 708A DVD burner -- died about a week ago. I had hoped that might have been the cause somehow, but I replaced it with the Lite-On DVD ROM and the computer still crashes. Also, FWIW I have Ubuntu Linux installed on a different partition of this machine (which I don't often boot just because most of what I do requires Windows) but maybe I could use it to somehow test the machine further? I would really appreciate any help with this really maddening problem. Thanks!