My Mid-2010 13" MBPro Core 2 Duo (P8800) spinng gear freezes on boot up. This happened with two sets of (2x4GB) 8GB G.Skill FA-10666CL9D-8GBSQ kits. What can be done to resolve this? MBPro is spec'd for a min memory speed of DDR3-1066. The G.Skill is DDR3-1333. Could either of these be a reason? Should I consider resetting NVRAM / PRAM?