I installed an MSI Lightning 7970 to replace my dual card - Apple 5870 and 5770 - setup, but I'm not seeing any noticeable speed improvement. Am I missing something, did I run the wrong test, or is there something else limiting the output? Most of my use is under Windows/Bootcamp, so for a quick test, I timed how long the 5870 and the 7970 took to thumbnail ~150 home movie files (720p/1080p AVC HD files) when opening the folder in Windows Explorer - both setups took the exact same time. On an older machine that went through an upgrade, this test produced a noticeable difference between the cards. I do not have an external PSU and am using two 6-8 pin connectors to power the card, deleted old drivers and installed new ones. I know there is a long thread about the possible damage after someone installed a 7970 in a heavy use environment but figured my usage does not come close to stressing the card.