Mac in the shop with a logic board issue.

So I havent even had my iMac for a year and I was told by Apple Care that my iMac had a major Logic Board issue and it would have to go into the shop for repairs.

So through the year I did notice that it seemed like it would take longer and longer to boot up as time went on. Then the other day I went to install a upgraded router and went to put in the disc. I would insirt the disc and it would come back out seconds later. I tried a few times until I finally restarted the Mac. It went to a white screen and never booted up. I called Apple care and they walked me though all the different ways to get it to boot. Nothing worked. So that night I had to rush my Mac to a authorized Mac repair center before they closed.

The tech said that Apple Care often says to the customer that it's a logic board failure and replacement will be necessary, but it's not always the case.

From what I described, can any of you tell what the logic board issue can be? As I said, nothing works and the white screen remains.

Thanks for your time.

Apple Care techs are pretty much Level 1. They hit a stopping point, and tell you to bring it in. At least that, is my experience.

What's the problem with taking it in and getting it fixed or replaced for free??