I have a 3 RAMs, 2x1GB and 1x4GB, but it appears that only the 2x1GB is detected by my computer. I thought that my 4GB DDR2 RAM is broken, but i saw a lot of threads that lead me to download CPU-Z to see if all the RAMs that are sitted are properly working. Then it that software, i saw that i have 6GBs of ram and it also appears in DIMM3 slot status that my 4GB is detected by my computer, but only the 2gb are usable. And it was also indicated at the Device Manager of my PC that it has only 2GB of RAM. My pc can hold up to 8GB of RAM which is 4x4GB, and i was really sure that it was compatible with my 4GB RAM. Is the card broken or what? Can someone help me to fix this?