1) To stop the endless restart loop, boot the computer into [i]Safe Mode[/i] by tapping the F8 key during the early boot phase (POST = Power On Self Test phase). One of the options will be the following:
[i]Disable automatic restart on system failure[/i]
Select this with the arrow keys, hit [i]Enter[/i].
2) Run diagnostic software on the hard drive. It may be failing, which is why your reinstallation of Windows fails.
2a) Download the free Seagate utility:
http://tinyurl.com/yvq99t
2b) Download and install the free application CDBurnerXP:
http://cdburnerxp.se/
2c) Create a [i]bootable[/i] CD from the Seagate [i]iso[/i] file using the following guidelines:
http://tinyurl.com/4f3coa
2d) Run the Seagate diagnostic utility from the bootable CD you created, and determine the health of the hard drive. If the hard drive is failing, replace it, and format the new hard drive NTFS using the Seagate utility before installing Windows.
Please post back in this thread if you need further assistance. If you succeed in resolving your problem, let us know what worked for you.
Rick/Portland, OR