Hi, I've had my current computer for about 18 months with a stick of 256 kingston DDR ram. I bought another 256 stick from a friend and I know that it is functional. When I put his stick in, the bios didn't recognize the second stick on bootup. I tried each stick independently and they both work, but both will not work together. I tried switching them in different slots, but I can only get one stick to be recognized. I have an elite group K7VTA3 motherboard with 3 memory slots and it supports up to 1.5 gigs of ram. Both sticks are DDR 2100. Any help would be much appreciated.