Hi. I previously had in my system a matched pair of 512 MB Crucial Ballistix PC3200 dimms on an ASUS A8n sli deluxe.One of them crapped out. I've just bought another matched pair and a single module to bring the total up to two gigs. The system now tells me I have these running in single channel only. As far as I know, all four modules are exactly the same spec, manufacturer, etc. If I run only the two new dimms it's dual channel fun. Any suggestions? Cheers.