Chosen Solution
I bought this RAM Crucial 2x4GB, but when I try to install 2x4GB on Macbook Pro it’s not starts and beeps 3 times and then off. My Macbook Pro works if I only put one 4GB module in lower position and a 2GB module in the top position, But, if I reverse things putting the 4GB module in the top position it will not start and beeps 3 times. Anyone have this problem?
First try both 4 GB sticks in the lower slot, one at a time, to make sure they are good. Next try just one of the 4 GB sticks in the upper slot, then try the other. If it fails, you have isolated the problem. Clean the upper slot with a contact cleaner and make sure all looks OK. Make sure you have installed all the software updates. If all this fails, live with 6 GB of RAM.
