I have a MSI K8N NEO4 Platinum SLI Motherboard and I originally had 2 X 512 OCZ Platinum DDR400 Enhanced Latency sims running in Dual Channel. I recently bought another dual channel kit 2 X 1GB OCZ Platinum Enhanced Latency sims. I would like to run them all and have 3 GB but not sure how to do that in dual channel. I tried 1GB 1GB 512MB 512MB but that severely degraded my memory performance as seen in the Windows Vista performance tests dropping from a score of 4.5 to 3.6 I removed the 2 512's ie. 1GB 1GB empty empty and my memory performance jumped up to 4.9 an improvement over my old 1GB configuration, but I'd still like to use it all if I could. Anyone know if this possible?