Identifying the problem with a dead 2010 iMac?

My old 2010 iMac which I handed over to a family member unceremoniously died today between uses.

In the afternoon it was playing games and the next time someone went to switch it on, it's dead as a doorknob. I've done all the usual tricks (resetting SMC, changing the fuse, trying a different cable, reseating the RAM).

Twice (out of many attempts) it activated the fans that seemed to go at full blast and that was it. Does this indicate anything in particular?

I guess the best thing to do would be to take it to the Apple store but the machine's over 4 years old now.

Intell said:

Apple will still service that machine for another year. It could be a problem with the logicboard or power supply.

Click to expand...

I was guessing it's one of those two myself. I guess I'll have to drag it into the local store if they can still fix it.

Thanks.