I recently ordered a 4gb ddr3-1600 sodimm 1.35v 204 pin stick of ram(part # CT3564257) online from crucial. This part was suggested by the system scanner as a recommended upgrade that was compatible with my system. I'm using window 7 home premium.
First, I installed it into the empty dimm slot. and Windows was unable to load normally. It rebooted automatically into startup repair mode, which could not repair the problem.
I ran bios and it recognized that I had the full 8gb ram installed.
I was able to load windows through safe mode with no problems and windows was recognizing that I had both sticks installed (2x 4gb)
Next I took out the old ram from the first dimm slot and installed the new ram there by itself. Again it could not load windows normally and went into the startup repair mode loop.
Then I ran mdsched to check for errors and it didn't find any.
I went to the Lenovo website and verified I had the latest bios and drivers, which I did.
Not really sure where to go from here, any suggestions or advice would be greatly appreciated.