No Display

maybe the graphics card overheated how long was the computer on for?

There is a possibility that the video card has fried in the process. I know that when my video card fried while playing COD:MW2, graphics started looking weird, mismatched colors and everything including just plain not working correctly under windows normal. If you have tried using a different video output with same results, more than likely the video card has failed and will need to be replaced.

One option is to borrow someone else's video card and see if you can get it to come back up with video first as a preliminary test. Or take your card and put it into a known working computer and see if you can even get the BIOS to show on another computer. However, I would lean heavily to a failure of the card in general.

Edit:

Forgot one more test... Hook your monitor to a known working computer as well, there is a slight chance the monitor might have had problems itself or the video cable, although you stated you tried different outputs. Either way, testing all possibilities will help narrow down the root cause first. But I don't think this is purely a windows problem but a hardware failure somewhere.

try keiichi plan and tell us how it went

Damn my impatient eyes...

Well, laptop, sometimes it might be due to accidental video switching, like the Fn+F7 or whatever the F Key that has the monitor Icon. The problem still would be the Card though if you aren't getting video trying to flip through the different modes the laptop should be able to offer and from the description, it suggests the video chip in the laptop might have fried.

One thing to note to your friend, generally you don't want to play 3D graphic games on a laptop unless it is one of those heavy duty desktop replacement kind. The mid and light laptops tend to have not enough air flow for the video chip to keep properly for 3D applications that the chance of blow it might be higher than you expect.

Try the Fn+F Key, see if it will switch modes, as Laptops of that sort with the VGA output sometimes can stick in a different mode. If you can't get it to display on anything, see if you can get HP to warranty replace the laptop if it is under a year or 2 old.

Edit: The other option is that there are USB-VGA adapters to at least get standard Windows video. However, do NOT use it for gaming. This should be only if you want to pull data off the computer and you don't want to try and pull the Hard drive out and try to extract the data through some other means.