I have a very old PC which has been working more or less ok till recently. Ok, so it's a P3-866, with 256 mb ram, a 32 mb GF2 video card, but it ran WinXP smoothly and I could use photoshop, office stuff and even play some games. Recently, I've moved and changed the hardware on the PC (took out the TV tuner and old Ethernet card and plugged in a wireless network adaptor). I guess that's when all my problems began. And these problems are very annoying: the bloody thing keeps BSODing, freezes, refuses to run photoshop, I can't watch videos larger than 100mb etc. The PC freezes when I'm browsing, checking my email, using Miranda, Winamp or Skype. Most BSODs are "irql_not_less_or_equal" and "page fault in non-paged area" (the second one I'm not sure). I often have to reboot the PC. For example, as I was registering, I had to go into Opera settings to allow cookies for these boards. When I tried to do that, the computer froze. You get the picture. I'm thinking maybe all these things happen because my hardware profile has changed and the XP installation (nearly 1yr old) didn't like that? I'm more than ready for a reinstall, I just want to make sure that I'm not doing something that's not going to work. I looked at the bios power management screen when I rebooted and wrote down what I saw. I don't know what to make of this, but hopefully someone will tell me if there is a problem with the PSU. Vcore 1.74v VTT 1.37v-1.53v (lowest & highest values I saw) 3.3v 3.05v-3.07v +5v 4.78v-4.81v +12v 11.49v-11.61v -12v -11.54v -5v -4.84v VBAT (v) 3.12v 5VSB (v) 4.80VCould someone tell me what I should be doing? Hopefully, I won't need to upgrade the whole thing. This would be nice but I can't afford it ATM. Just to add a couple of points (after reading another thread): 1. I can start Windows normally. The problems don't occur until I run an application. 2. Event log shows nothing. No error reports whatsoever. Just the usual "service stopped", "service started". 3. I'll have to wait till the next BSOD and will write down what it says exactly. That shouldn't take too long. 4. Psu readings as above. Speedfan shows the same thing. 5. System temperatures are OK (again, as per speedfan). 6. System restore disabled, so can't undo. 7. Will run memtest over the weekend. Sometime the system runs for the whole evening without a sign of trouble, sometimes it freezes right after start-up. Today, I could successfully burn a CD, but had the PC freeze when using Opera. So it all seems pretty random to me - except photoshop: it can never launch.