Computer problem in 2004 Chevy Cavalier?

For a while I was having a problem every now and then once warm weather days hit where I crank my car, go somewhere, get there, turn it off, and then have problem getting it started again, it wasnt too bad and after 3-4 tries would start, figured it may of been a fuel related problem, it went away and the problem started occuring again every now and then.

Fast forward to today the car was hesitating close to the destination, 2 hours later tried to crank it, it roll over but will not start, their is no power going to gauges when you turn the key or any lights on the dash board. Other things like hazard lights, AC, radio, wipers and all would continue to function with the key turned.

Took it for a diagnostics (tire kingdom) as they tried to figure it out, fuses seemed to all be good, they then tried ODBII computer and got no power to it, they said their was no power going to the coils either.

Is this computer related? I got someone working on it now, if he gets it up and going or not I dunno, but he said if it was the computer (I guess the ECM thing that sets on top under the hood toward the back) their would be no power to anything at all.

I am stumped, any ideas?