After updating a software using the software updater, when my macbook 15" 2011 restarts, it gongs (startup sound) , then is followed by 3 beeps then shuts off, turns on gong, turns off. it does that around 3-5 times then it finally powers up normally. I have read around, is it my RAM? I did upgrade to 8gb total, (4 each slot) when i first bought it, and it was fine then.