Please open another thread u cannot post ur thread in others thread.

Plz check the RAM remove it and place it again, if this doesn't work remove the Processor and place it again, but be careful

Have u installed any software or hardware(drivers) b4 this problem, if so try uninstalling it in safe mode as u said u were able to boot into safe mode

U said u have created a startup disk is it...

Many time this happens if the HDD is not detected

Make one last atempt b4 buying a new HDD.
Deassemble ur system discharge each and every component on the board by touching the pins with a screw driver, remove the bios chip, again put it in, change...