[CaptFiero]

There are about a dozen steps to go through. But here are the simple ones.

First turn off the computer power supply.
Then unplug the computer from the wall.
Now as dumb as this seems, try to turn the computer on with the front power bottom.
You should hear a slight noise as the computer empties the power supply.

Now plug in the computer and try to boot.

If it still locks.

Shut it down and unplug the power again.

Now remove the side panel, I am going to assume you don't have a raid array as if you did, you probably would know enough to troubleshoot this on your own.

First unplug the power and IDE/SATA cable from the CD/DVD rom drive.

Ok do you have more than 1 Hard drive in there. If you do, unplug the power and IDE/Sata cable from the 2nd drive. IF you don't know which one is the main drive. Just unplug one and try to start the computer. If it locks up, try the other one, if it does not lock up, however attempts to boot and gives a "incorrect boot device" you could be screwed. As that means you unplugged your main boot drive and the computer is now trying to load. That means your main drive is FUBAR.

If the machine locks up again, instead of giving you a boot error, swap back to the other hard drive and attempt to reboot. If you get into windows, shut it back down, re-attach the CD/DVD rom drive. See if it boots.

There are about a dozen tests you can do, however these are the most simple straight forward tests.

You can grab Memtest86 to check your ram, you can get HD testing software from your HD manufacturer.

While you are in there, give every can you can get to a spin, if its seized it can create a load on the PSU high enough to cause boot issues.

Well thats the easy stuff. Hope I helped more than confused you.