View Full Version : weird graphical glitch on Start up?

Aug 29, 2013, 08:55 PM
So I just upgraded my 27" iMac to Mountain Lion last week and now every time I boot up my mac there's this weird rectangle graphic distortion that pops up right as the apple sign appears. After it loads everything is fine and I can use my mac normally. Im just curious what it is. It never happened before Mountain Lion. Any ideas?

Mac specs:

27" iMac
OSX: 10.8.4
Processor: 3.4 GHz intel core i7
memory: 12GB
graphics card: AMD Radeon HD 6970M 2048mb


Aug 29, 2013, 10:26 PM
Strange indeed. Try a SMC reset and see if that fixes it.

Oct 27, 2013, 08:27 PM
I am seeing a similar issue during boot on my MacBook Pro 2011. Faulty GPU?