Hey everyone.
I have had an eMachines E4252 computer for about a year and a half and about a month ago I got this really weird problem with it. Whenever I start up my computer it will shut down when it tries to start windows. After trying multiple times, I started my PC in safe mode then tried a system repair and restore. On all of them my PC shut down while loading them up. I tried to reinstall windows with a disc but that didn't work either. Then I tried to start my computer with optimized settings on my BIOS and when that didn't work I changed it to the fail-safe setting but it still wouldn't work! I tried disconnecting things (keyboard, mouse, speakers etc.) but it still wouldn't work so I checked inside and tried switching out power supply, ram, everything, apart from the motherboard and CPU. I also do not have any viruses because I remember checking the before and not finding any.
OS is Windows Vista

Thanks for reading and hope you reply soon

Hmmm, well, you swapped RAM and the PSU so they are likely ruled out. Note when Windows starts, the first thing it does is load up drivers. The fact you were able to boot into Safe Mode further points to drivers. Make sure you have disconnect extra drives, card readers, or other device not needed for the computer to boot.

Did you try a different graphics card?

No, but I have now and it still didn't work. Also, I think I should have used better grammar because you mentioned that I managed to boot using safe mode but I didn't, i really should have made it more clear.
anyway thanks for replying.

If the new graphics card does not work, and you tried a different PSU and RAM, then I am afraid that points to the motherboard. Sorry.

So I need a new motherboard. Cool, it could be worse. Thanks for your help mate.

That's what it looks like. It could certainly be the CPU, or something else plugged into the motherboard dragging everything down through a short, but it looks like a bad motherboard from here.