Vertical bars on display -- hardware problem?

[smirk]

My mid-2011 iMac 27" suddenly started spontaneously rebooting over and over. As it booted, it looked like this:

It seems like a video card issue, right? Especially because it would look like this even before the OS started to load. On a lark I booted from an external drive, and it came up fine, without those bars.

I haven't had a chance to really troubleshoot it yet, but is there any way this is just a software issue? Any ideas how to troubleshoot it?

Thanks!

 

[MacPro73]

Guaranteed video card issue. There was a known issue with this model : https://support.apple.com/en-us/HT203787

If you're lucky, Apple might even cover the repair.

 

[maflynn]

It seems like a video card issue,

Yep, its the GPU

Call Apple to see if they'll do anything for you. I know there's a repair program for MBPs, I just don't know if that extends to iMacs

 

[smirk]

Thanks everyone! Here's my report of what happened. I took it to the Apple Store and the video card passed their hardware test, as well as the extended stress test they ran on it.

However, it turned out that the HDD fan motor failed the maximum speed test. It apparently was gunked up with dust. They vacuumed it out (through the vent?!) and everything seems to be working now. The tech said they've seen this before: the video card sits right next to the hard drive, so if the HDD gets too hot it can affect the video card.

I have doubts that the fan is truly clean, since they only held the vacuum up to the exhaust vent. When I install an SSD soon, I'll remove the fan and make sure that whole area is clean.