I find I have to use the recovery CDs. Try that next.
I have a Lenovo desktop 8139 with Windows XP. It will boot up to the bios fine, it will run Knoppix fine. I took the hard drive out and ran Maxtor tests in an external adapter. Hard drive passed fine. I select the option to boot to safe mode or regular and the result is always the same, a black screen. I ran chkdsk on the drive also. The IBM f11 option (which I hate!) did not work either. It tries to recover but then fails. Right now I am running a Antivirus scan with Avast on the drive. Any suggestions? Corrupt MBR? No error messages or blinking lights like missing OS when booting, just a black screen.