While your thinking I'll keep writing. http://www.google.com/search?q=C000021a finds the causes are far too many and given your post it could be the heat, bad spot on the hard disk, RAM, BIOS settings, overclocked machine, HEAT or you left some USB device plugged in during the install.
Given there are dozens of causes, think over what was plugged into this machine when you first installed XP. Unplug that RAM, USB things and test the hard disk then try again.
Be sure there is no overclocking going on and you did this -> http://reviews.cnet.com/4520-11319_7-6240575-1.html
Bob
OK I was having some problems with a virus on my compute3r so thankfully backed up all my files and decided to format and start fresh. So I put my XP disc in and get to the screen that has the 3 options that are something like Format (Quick), Format and install over(sorry I cant remember e3xaclty as I am at a fiends place at the moment. So I choose the format option and it just stays at 0% And doesnt move. So I reset and try the quick format and this works fine but then after some setup screens I just get the blue screen with STOP: c000021a {Fatal System Error}
The windows subsystem system process terminated unexpectedly with a status of 0xc0000005 (0x7c9106c3 0x0069ed04)
The system has been shut down.
I really don't have any idea what to do next so any help would be great thanks.
Chowhound
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