n0nsensical

Basically it means two DIMMs can be accessed at the same time, increasing bandwidth. Theoretically doubling it, but realistically not that much, and can be almost no difference in the actual performance of apps that aren't that starved for bandwidth. (like many games) Overall it's still beneficial and more or less free, so there's not really any great reason not to have it in a new performance system. The only reason I'd go single channel is if I knew I was going to be adding more RAM in the near future so that in the end I'd only have two DIMMs rather than three or four. (generally you get better performance out of two than more assuming the same amount of memory, plus you have more room for further upgrades with more open slots) For example, if I was getting 512 MB now and adding another 512 in a month or two, I'd buy a single 512 MB DIMM each time rather than buying two 256 MB DIMMs right away.

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