I just tested this on an AMD based PC with XP Pro SP3 and it booted back up OK. Mind you the hard drive is in good condition. If SP3 couldn't write to the hard drive properly when it was installed you may still have problems. You may have to do what I suggested above to retrieve the data. I will add some links below for testing the hard drive.
Boot into Safe Mode
Click Start, and then click Run, type appwiz.cpl and then press ENTER:
Click to select the Show Updates check box.
Click Windows XP Service Pack 3, and then click Remove. Click OK to remove the files that won't work without SP3.
Click Finish to restart the computer after the removal process is complete.
You can use the Hard Drive Makers Testing Utility to Test the Drive
Hitachi / IBM - DFT "Drive Fitness Test"
http://www.hgst.com/hdd/support/download.htm
Works with all manufacturers
Western Digital "Data Lifeguard"
http://support.wdc.com/download/index.asp#dlgtools
Works with WD drives only
Fujitsu "FJDT"
http://www.fel.fujitsu.com/home/drivers.asp?L=en&CID=1
Works with fujitsu models only
Samsung "hutil"
http://www.samsung.com/Products/Hard...ties/hutil.htm
Compatability unknown...
Seagate "Seatools"
http://www.seagate.com/support/seatools
Works with Seagate drives only
Keep us informed as to your progress if you require further assistance.
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