1 gb dual channel better than 1.5 gb non dual channel?

[kisrum]

Until now I've been running one Micron 512 mb 400 mhz PC3200 DDR RAM in only one of 4 available slots on my intel D865 PERL motherboard. I went and bought a new pair of Kingston 512's for Christmas, and will be putting them in the proper slots soon.

Would I be better off taking the old Micron out completely, that is, running 1 gb of dual channel RAM, or sticking the leftover 512 in a third slot and (probably) messing up the dual channel feature, but running 1.5 gb RAM? Fry's Electronics guy said put all three in, which made me think I'd better go with two.

I know there's probably a better forum for this question, but this is the only forum I spend much time at. I guess I could just run some simple tests on games or something but would appreciate input. Thanks.

[rallynavvie]

Unless you are running an 800 FSB processor I don't think it matters if you are running your memory in dual-channel or not. 800 FSB uses the memory's bandwidth of 400 MHz and doubles it, when installed in pairs per the board's instructions, for the 800 MHz speeds at 1:1 (which is what you want).

If you have a 533 FSB chip then your memory is probably only running at PC2100 speeds OR it is running at 4:3. If it's running 4:3 then you aren't running dual-channel and it won't matter if you have three sticks in. If you're running 1:1 then you do have to run dual-channel in order to get the full bus speeds from your processor.

You could even be running a 400 FSB processor in which case the memory is running 1:1 and it won't matter what memory configuration you go with as long as it's all PC3200. Dual-channel wouldn't really get you anything since each stick of memory constitutes your bus speeds itself.

Safest bet would be just to use the two matched sticks though. I've never liked mixing memory brands in any of my computers.

[kisrum]

Thanks very much. My motherboard is 800 mhz FSB so the dual channel should work. Right now I'm running 1 gb paired pc3200. Guess its working.