I have an XP (sp3) PC that is consistently hitting BSOD resets 2-4 times per hour. Crash frequency is the same whether programs are in use or if it just sits there idling in Windows without anything else having been open. The error code starts BCCode: F4 BCP1 00000003. (I can post the rest if needed.) I've tried the following without seeing any change: - Swapped the two RAM sticks, also ran each on their own. - Cleaned the contacts on the RAM and blew out what little dust was in the case, with particular attention to the slots for the RAM and heat sink. - Temp doesn't seem to be a concern. The computer has 4 case fans plus the heat sink and power supply fans and all seem to be working just fine. (The power supply fan makes a somewhat louder "spinning up" sound on reboot but then goes back to normal immediately after.) - I pulled a recent batch of dmp files but only my Win7 machine has debugging tools installed and I'm getting errors that seem to be related to reading XP .dmp's on a Win7 and not being able to get the correct symbols. I have a separate folder for Win7 symbols and WinXP symbols on the Win7 machine but I get errors whichever symbol folder I map to when trying to view these .dmp's. - I've tried running the full /r /f chkdsk but haven't been able to complete one before a crash yet. (Farthest I've gotten is 36% in step 4 of 5. It seems like chkdsk could be getting stuck at 36% as it is spending a "long" time there but I'm not sure if it just needs more time to get past there than the crashes are allowing.) - As far as I know the PC has never been dropped/struck/other things that might point more at a motherboard issue. - I tried switching off things like caching/shadow in the BIOS memory settings. So far nothing I do seems to change the behavior. Unfortunately I don't have an extra power supply to try swapping in. I'm attaching the last five .dmp files but have lots more if needed. It's an incredibly frustrating problem. Thank you for the help everybody!