WindowsXP won't start

[cryogenic]

I have emachines T6520 with 480W PSU installed. Everything been fine, but lately my windows (or something else) stopped working correctly. Instead of going to windows loading screen my screen just goes black and _ blinks at the top left corner of the screen. Also sometimes windows does turn ON and everything seems fine, but after a restart same problem occurs.
Is that something with windows or hardware? I would appreciate any help.

 

[tpfagan]

Can you get into safemode? Press F8 right after it boots - but before you would normally get the windows loading screen.

 

[iss]

Sounds like hardware. the first thing I would do is run your hard drive makers diagnostic program on the drive. what you describe can happen when a drive is starting to fail. and I would back up any important data on that hard rive ASAP.