Restarts on start-up

Im trying to fix one of my friends computer and it keeps resetting during the Windows XP boot screen. I cant access safe mode. I tried to reinstall windows, but I didnt have a bootable copy. I tried booting it from a floppy but for some reason it does not seem to recognize it. Can someone help me out?

Im not really sure about the specs, but here:

M7NCD motherboard
AMD duron something
20gb maxtor HD
1gb ram

this computer seems to be about 2-3 years old.

can you run memtest86? (www.memtest86.com)

memtest?

how can i run the memtest? I dont think i can even get a prompt

does the system complete the POST (power on self test)? if it does not complete the POST, you have a hardware problem.

the POST is basically a procedure that the computer goes through when powered up to ensure that all hardware devices are functioning properly. a system with a hardware problem may not necessarily fail the POST. if the POST does fail, it means that there is a hardware problem that is preventing the machine from even attempting to continue to start. not all computers display detailed information when performing the POST.

does the computer in question have a floppy drive? if so, do you have another working system with a floppy drive and internet connection.

memtest86 can be run from a CD or floppy drive. follow the instructions on the memtest86 website.