MacBook Pro RAM upgrade causes endless reboot I recently acquired a MacBook Pro (13-inch, Mid-2010) that has 4GB RAM (2x2GB) and according to Apple, the unit should be able to handle 8GB RAM. I bought 2 DDR3 PC3-8500 4GB from memorystock.com and when I installed the pair of them, the laptop would go into a continuous reboot cycle. I have checked the EFI and SMC. The EFI required an update, which I performed. The SMC is up to date.

Here's the weird thing: I have gone through every permutation that includes both of the new RAM sticks in combination with one of the old 2 GB sticks. The system boots without a problem if it's only 6GB total. If I use both 4GB sticks, endless loop.

I'm at a loss.
Well, it turns out that after I RMA'd the RAM that I got from Memorystock.com, the replacement RAM works fine.

Problem solved. I just thought that I'd pass that along...