I recently had 4 ram sticks each with 4 gigs. but had to take two out because they went bad. Just recently, My computer would boot up normally but as soon as it passes the Welcome screen it would just go pitch black and I can only see my cursor. It would give me memory issues. So I took out another ram stick, now I have 1. I can boot it up now but everything is so alot slower and alot less smooth. I'm not sure what is wrong.