I am using Corsair Twinx 3200LL, 2 512mb modules. If you are running a cpu with the 800mhz fsb, your overclocking options will be limited. The 875 chipset doesn't particularly do well overclocking and it doesn't like low latency memory. I have a 3.0c processor. The memory runs at 2-3-2-6 which is the manufacturer's spec and I have the fsb at 210. I probably could bump up the fsb a point or two but would probably suffer with instability. You might be able to get the fsb higher with pc3500 or better but you will have to relax the memory timings. In any case, the mobo chipset will be your limiting factor.