hard drive replacement killed the laptop?

alright, I'm posting on behalf of a friend(doing chat on facebook..), who is trying to replace the harddrive on a windows 7 laptop.

now.. installation of the new drive did not go to plan, so he tried to put the old one in, and the computer apparently took this as cause to commit seppeku if you will.

we have tried everything, up to and including testing for a bad mobo, which I suspect it is.

all he's getting is a power light, not even the screen's backlight is coming up.

attached is the system specs below.

intel dual core 1.75, 160gb hdd, 2gb ram, compaq presario cq60


help?

Is the computer at least getting to the bios screen ?

no, and thats the first thing he tried even before I suggested it.

update: harddrive is loading. it just wont enter windows.

also, it is flat out refusing to load to bios.

If the new HD is a new Raw HD it won't have any Windows operating system on it.

He`s pushing the correct key to get into the bios ?

In no way simply exchanging a hard drive should have messed with the bios.

Could you elaborate on what you meant by "the new hard drive install didn`t go as planned"

hey doz, I figured these guys could help since I'm drawing conflicting conclusions here. they should have you sorted to rights if not soon, then in a reasonable timeframe.

DocBrown said:

If the new HD is a new Raw HD it won't have any Windows operating system on it.

He put the old back in.

hence... the computer trying to commit seppeku. I've never seen this kind of behavior before. so, I sent him to where I go when I've got a problem.