The motherboard talks?? Umm.. I've never had this problem. To get to the bottom of which part is causing the problem, you'll have to pull out each part and put it in another working computer to see if that part is the problem. Just keep doing that until you narrow the problem down.
But, it sounds like your mobo needs to be replaced. Check out this link: (Note, when the page first loads you have to wait a few seconds for the ad they display to go away)
http://www.techsupportforum.com/hard...-cpu-test.html
The guy had a similar error "System failure, CPU test" and after narrowing it all down figured out it was a bad mobo.