BleepingComputer.com: ASUS P5ND won't get past intro screen

My PC - which has worked just fine for over a year - now won't boot up. I get the ASUS P5ND intro screen at which point it freezes. Pressing DEL on start-up gets me the "Starting setup..." screen at which point it freezes. Pressing F8 gets me the "Starting boot options..." screen at which point it freezes. Pressing TAB gets me the POST BIOS screen at which point it freezes. I've tried resetting CMOS and that didn't work. Also tried different memory configurations and that didn't work. Any ideas??

Try a different PSU?

No STOP error messages?

Try running chkdsk /r from the Recovery Console of the XP CD?

Louis