Windows 7: HP CQ60 labtop won't boot or start

Hi i was running xp everything was fine, I decided to installed fresh windows8 it was running normal for three days I turned on as normal all i get is black screen nothing else i can hear cpu and fan running. i tried to re-install xp it won't boot can't enter the bois to run out of Ideas now any help please.

do you get the bios beep
and try removing the ram and reinstalling the ram

Work through these steps which are similar for Win8: Troubleshooting Windows 7 Failure to Boot

After cleaning any infection, you'll need to boot the Win8 installer or Repair CD to run Startup Repair repeatedly to see if it will start. If not try the other steps in tutorial.

It would have been better to shrink XP to install to separate partition from booted Win8 installer. Personally I would not go back to a dead OS now but either try to repair or reinstall Win8 from boot as it should have been installed to begin with.

If you can't boot the required disks to disinfect, repair or reinstall then reset the BIOS to defaults: Clear CMOS - 3 Ways to Clear the CMOS - Reset BIOS.
Try using the one-time BIOS Boot Menu key to trigger the disk or flash stick. You will have to get the disk or stick booted to repair, otherwise we'll need to take other measures.

to the thread starter with an ego problem:

Use PartitionWizard to wipe the disk clean, then you will be able to install XP.

Free download Magic Partition Manager Software, partition magic alternative, free partition magic, partition magic Windows 7 and server partition software - Partition Wizard Online

Thanks for your replays guys I've tried PartitionWizard did not work because there is no boot option there is no option like press any key to boot from cd or DVD is just black screen nothing else happening.as gregrocker said i'll try to Clear CMOS and see if that works.

So you are no longer wishing to repair but now want to wipe the HD to Clean Reinstall - Factory OEM Windows 7 ?

Burn PW ISO to CD using ImgBurn.

Try tapping the one-time BIOS Boot Menu key given on first screen to trigger the CD drive.

Highlight the target HD then from Disk tab select Wipe HD.

This should force the Windows 7 installer to autostart on its own.

thanks mate still no luck is not booting from CD, and no access to BIOS just Black screen tried to connect to monitor but still was black. Thanks anyway.

Are the fans spinning and processor or HD lights showing any activity?

Yes the fans spinning and processor I can hear that, also the switch on off light is on, I'm trying to Clear CMOS -now I've removed CMOS battery - waiting for 1hour then i''ll put back we see if that will Reset BIOS to Factory Defaults.