Chosen Solution
My system is not recognizing both RAM memory modules anymore. It initially had two 1GB RAM memory modules, which I replaced by two 2GB RAM memory modules, and everything worked fine for months. It fell on the floor three weeks ago, and since then, the OS only recognizes 2 GB out of the 4. It always displays one slot as empty. I have tried changing the configuration, keeping only one memory module, testing in both slots, etc, and couldn’t draw a conclusion, because: With both memory modules, I got to a point where system was booting with only that memory module. Thus both memory module seems to work.With both slots, I got to a point where system was booting with a memory module only in that slot. Thus both slots seem to work.Conversely, while changing and re-testing some configurations I had already tested, I ended up having a configuration fail which had previously worked, with both memory modules and both slots. I have tried the following: Reset SMCReset PRAMCleaned up RAM pinsLoosen RAM socket screwsRemove RAM socket screwsDisconnect hard drive, and boot from USBInserted 2mm plastic card in between both RAM memory modules How to troubleshoot from then on ?
Sorry to say you shocked the logic board ;-{ Not much you can do here as the socket is likely damaged and or the logic board wiring within the sandwich has been damaged. If you look at your case you might see a dimple just over the socket. If you look inside the mid rail has a black plastic pad to cushion the case bottom from hitting the logic board. Time for a new logic board or system.
