Dual Channel mode will give you around a 12 to 15 percent performance
increase. Here is how Kingston defines dual channel mode in their glossary.

Dual Channel
Based on the dual channel system board designs, memory modules are
installed on two separate channels, each with it's own access route to the
memory controller. The dual memory channel design doubles the peak
bandwidth of single memory channels. Best results occur when a matched-pair
memory kit is used ensuring that the modules are identical.

I have DDR Dual Channel support on a ASUS P2B Deluxe, and an Intel 865PERL
motherboard. In order to obtain Dual Channel access on these boards ALL
installed DIMMS, in both channels, must be matches.

This means that say in Bank one, channel one, and Bank two, channel one, I
have two exact DIMMS. Everything on the DIMMs have to match. Circuit board,
chips, everything. The two different channels can have different DIMMS, but
within the channel, the DIMM must be an exact match, that is supported by
the motherboard. At POST I see "Dual Channel Mode" telling me it is working.

If you have two matching dual channel supported Dimms installed in Bank
one, channel one, and Bank two channel one, ...and then stick a single
DIMM, OR a unmatched SET, in Bank one, channel two, OR Bank two, channel
two, then you will gain the additional RAM, but will loose dual channel
support, on the motherboard.

If you buy your DIMMs from a memory manufacturer, like Micron Crucial, then
you don't have to worry about the match as long as you buy the same two
model number DIMMS. But other kinds of RAM, like say Kingston, who assemble
RAM from various suppliers, may not be EXACT matches, even though they are
the same product number.

This is why Kingston sell matched sets, at a premium, and have a notice, on
the retail box of single Dimms that states, "Does not support Dual Channel
Mode". So with non memory manufacturers, it is a crap shoot whether or not
two random Dimms, will support Dual Channel Access.

If you have dual channel mode in one bank, you must have it working in
other banks if you add additional memory. You can not have it supported in
channel one and then add a non matching set, in channel two. It is a all or
nothing sort of thing. Of course, the final arbiter is going to be your
motherboard manual, which will tell you exactly what memory configurations
it will accept.

Rode
The NOSPIN Group
http://www.freepctech.com/rode/



>hi list,my pc has 512 megs of duel channel ddr ram.2 -256 k stixs. the
>retailer where i was planning to get another 512 from ,informs me that if i
>instal either a 512 or 2-256 sticks,that they have to check to see if they
>match and are duel channeling.if not i cant use my original 512 and need to
>buy 1 gig or 2 new 512 sticks.is this true or aload of crap to sell ram?
>
>hans--regina sk.ca

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