Hello everyone, Hopefully someone will be able to help me. I have just purchased two additional sticks of 1GB ram to put into my system. I purchased identical ram to what I had before Geil DDR2 800 (GX22GB6400UDC) and when I put it into my computer, the computer does not post. I have tried with 3 sticks and it works fine but as soon as I add the fourth, it's down. The only thing I see different is the color of the heatsink, the original ram is metallic orange, the new ram is plain orange. It also shows different timings 4-4-4-12 and 4-12-4-4. Besides that they are the same. Thanks!!