27in iMac dies on startup

[rwm514]

Just today my 18 month old iMac died while using it, it just went black, i could hear some faint noises from it though. I held the power button down for about ten seconds and it seemed to shut off. I held it down again and it lights up with the apple logo but within seconds goes black again. I repeated this cycle a few time to no avail. Any suggestions on what could be wrong? A fix? Apple store is two hours drive from me. Thx Rob

 

[omvs]

Could be a fan is stalled or something is stuck in it - machine is overheating, and shutting down. We had something similar happen to a PC at work - it'd fire up, then stop working after 5 minutes. IT pulled it apart and showed me a power cable that was stuck in the graphics card fan.

I would recommend taking it to the store (or authorized repair) versus trying to do anything yourself.