dual channel memory

[Buddy Mills]

Hi,

Can someone explain to me exactly what dual channel memory is? I know that
socket 939 boards can use it. I'm wondering if it's something that's
enabled by the motherboard( will standard PC 3200 run in dual channel mode)
or do you have to buy dual channel memory? I have an asrock k8 combo-z
motherboard that has both socket 754 and socket 939 on it. So when I'm
upgrading to a socket 939 processor will I just be able to move my Corsair
PC 3200 memory over to the other slots for the 939 and have it run in dual
channel mode? Thanks in advance for your assistance.

 

[Bob Knowlden]

"Dual channel" uses two ordinary DDR DIMMs in a parallel fashion to give a
128 bit wide path to memory. (Single channel is 64 bit.) It may not quite
work out to a 2X performance factor, but it gives nice numbers in
benchmarks.

The DIMMs must be the same size. It might be a good idea if they are
identical (which is what you get in a dual channel kit), but it may not be
necessary. I'm running a pair of generic 512 MB DIMMs on an Asus A8V (Socket
939) mainboard. The DIMMs both use Samsung chips, but they were purchased a
few months apart, and the chips have different part numbers. Works fine,
although it wasn't guaranteed to work.

I see that the K8 Combo-Z has separate memory slots for the two CPU sockets.
There are 3 slots for the 939 socket; You probably have to use 2 slots to
get dual-channel operation. (I have read that some nVidia chipsets support
dual-channel without requiring paired memory, but the chipsets only support
Athlons that have no native dual channel capability. If that's confusing,
it's because I'm confused.)

Address scrambled. Replace nkbob with bobkn.

 

[Buddy Mills]

Thanks for the explanation. That cleared it up for me.

Buddy