I just got my ram from OWC (8gb) and installed it. When i turn on the computer it doesnt load and goes to a black screen and says "No bootable device -- Insert boot disk and press any key". I restart and hold the 'option' key and im able to select the mac HD as a bootup and it boots fine. Checked and it shows I'm running 8gb of ram. Same thing happened when i tried putting in the OEM 4gb ram. Anyone know what could be causing this problem?