Sudden iMacPower Loss when Scrolling
My mid-2010 iMac (2.8 GHz Intel Core i5, 16GB Ram, ATI Radeon HD 5750 1024 MB) has an intermittent problem where it will suddenly lose power and crash. The common denominator in terms of when this happens seems to be related to graphics-intensive tasks, such as fast scrolling through a lot of image thumbnails in LIghtroom or Bridge, but the other day it happened when I was scrolling horizontally in an Excel spreadsheet. It has also happened once when watching a movie on DVD. Any ideas on what might cause this? Graphics card? Motherboard? Power supply?