I've some problems getting 4GB DDR2-800 RAMs. Currently, I've one 2GB DDR2-800 connected, working perfectly. But when I connect another RAM of the same type with the same bus speed (Kingston KVR800D2N6/2G, the computer fails to boot. My motherboard is Intel DG41RQ. On the Intel's website, it says that the mobo can support 8GB of Maximum RAM. I'm only connecting 4GB with 2GB, same type, same bus speed in each slot. What could be the problem?