I have 2 sticks of ram (2 gbs each). I noticed recently that my computer seems a bit slot with processing, so I checked my computer properties and noticed only 2 gigs of ram show. Then I checked bios to find that it says Memory Bank 2 says not installed but when I removed stick from bank 2 and leave a stick in bank 1, I get a beep when I try to boot up. What is the culprit here? Help!