A few months ago I kept getting messages that my virtual memory is 0, and that I should set it. However everytime I try to set it, it just resets it to 0 every time I reboot the laptop, even when i set it to system controlled VM. Also I kept getting POWER_STATE_FAILURE BSOD's everytime the laptop rebooted. I checked for unsigned drivers using sigverif, and discovered atapi.sys was unsigned. I didn't really know what to do about it, so recently I reinstalled XP, well actually upgraded from XP home edition to Professional edition as I thought this may sort the unsigned driver problem. However, now that XP pro is installed, the laptop doesn't actually boot properly at all. It gets to the Windows XP logo, the progress bar doesnt animate and then it BSODs straight away. I think the atapi.sys was something to do with the CD rom drive, and may have had something to do with it as the laptop doesnt even boot to windows setup with the disc in the drive (CD-rom is 1st priority BIOS). I dont have a floppy drive in the laptop so I cant create boot disks. I dont know how to access anything with a CLI or something to type commands. I really need all the data on the HD too, so I dont want to format it or anything. Can someone please suggest something? Thanks