Late 2012 27inch new iMac - error code -5010D

Hi,

I bought a new iMac 2 month ago, hardly been using it except for watching movies and surfing.

After a few weeks, it started acting funny: It gave me the grey startup screen with a blinking folder with a question mark. Upon next startup, the folder was gone and I managed to startup fine.

Then it would start freezing and working on any app I used: I reinstalled it (it took over 4-6 hours to reinstall mountain lion).

After I reinstalled it, it was working ok for a while. But then it really started acting up: it would freeze if I clicked on anything, internet, any apps, and the rainbow spinner would start working. I could still move around the spinner itself, but nothing would work. Even the apps (in the dock) would freeze.

I have moved house now, and it worked brilliant for a morning. Then it went back to the rainbow spinner and freezing. The SPOTLIGHT magnifying glass would show the wrong text, instead of Spotlight, it wrote: Search_Bar

I have tried:

1. rebooting from cmd,opt, p, r (for pram) - all fine

2. disk utility testing - all fine

2. hardware testing: d. This gave me error code: -5010D and the screen is frozen in grey background (attached image).

Any idea what is going on? I cannot find any info about -5010D online.