Random Shutdown of desktop when backspace is pressed

[Boozinberry]

So I've done some searching and I've found very little helpful information about this subject. My desktop is a HP and I'm using the Windows 7 OS. Doesn't matter what I'm doing rather it be on a web page making a post or just on a new text document, whenever I hit my backspace key on the keyboard my computer will just shut down. It also sparatically happens when I hit ALT or even ENTER. Anyone have any theories?
Oh and I've tried exchanging the keyboard as well and running virus scans such as Microsoft security essentials and Mal-ware bytes.
If anyone has any info for me it would be greatly appreciated thank you.

[rubberman]

Has this been happening since you got the system, or only recently?

[Boozinberry]

Has this been happening since you got the system, or only recently?

Started about 3 weeks ago now. I've had the system for a little over 2 years and it's never had these problems before.

[Bal]

Try changing keyboard from a friend or another PC and see if it still does it.

[jingda]

Does other pressing other keys on your keyboard trigger this problem. It may seems like your computer is worn out and needed to be send for a repair.

[Boozinberry]

Try changing keyboard from a friend or another PC and see if it still does it.

In my original post I stated that I had already changed the keyboard but thank you for your input.

[Boozinberry]

Does other pressing other keys on your keyboard trigger this problem. It may seems like your computer is worn out and needed to be send for a repair.

Yes Jingda sometimes pressing the ALT key or pressing ENTER will also trigger a shutdown. Sadly the computer is no longer under warranty and this doesn't seem like it just is worn out. It started not long ago and I feel as though it is a virus however I've not found anything with scans. If anyone knows anything about a virus that is doing this or a way to find viruses other than a simple scan it would be much appreciated. I am at my wits end.

[rubberman]

Best guess? Your keyboard controller is fubar. Are you using a PS/2 keyboard, or is it a USB keyboard? If PS/2, then try a USB one (no keyboard controller). If it is a USB keyboard, and your system has a PS/2 keyboard port, then try one of those. If USB and no PS/2 keyboard port, then I'd think about trying to reinstall the operating system to see if that fixes things.

[jingda]

What is with the negative rep on my post above. Most posters tend to forget about including all information in their post. I did read your first post and was double checking. If all other keys on your keyboard is having problem, it may seems your computer does not have the require power supply to power the computer. It can be an overheating issue too.

Did you add any new hardware components recently?

1) Do what rubberman said

If that works, great. Does not than try these

1) Open ip your computer case and see whether there are any damaged or faulty components. Especially the motherboard
2) Clear your heatsick to see if there are any dust in there.

[Bal]

If it is a USB keyboard, did you change to another USB port ?
Also it mayeb worth looking at
http://www.daniweb.com/hardware-and-software/microsoft-windows/windows-nt-2000-xp/threads/311695