When I try and put two sticks into slots 1 and 2 and or 3 and 4 the computer doesn't POST. It gives a C1 error code. It was working before so I don't know what happened. Here is a picture of what i'm talking about (the only 2 stick combo that works). It boots fine with the setup I have now, but it doesn't work with dual slot configuration. I have tried every combo and 1 stick works fine in slot 1 and 3. I have cleared the CMOS also using the CMOS switch and when that didnt work then I tired removing battery and moving jumper over.