I restarted my pc the other day and the POST lights hung on lights 3 and 4. which is a RAM error. I troubleshooted for a while and I can only get 1 of my 4 1gb ram sticks to work. It will work in any of the 4 slots. NONE of the other sticks work by themselves or paired with the good one. How could it be that 3 sticks just magically dont work??