64 bit vs 128 bit memory on nforce 2 ultra...

[Putz]

Curious

Main Memory
Supports six memory banks using three 184-pin DDR DIMMs
Supports up to 3GB PC3200/2700/2100/1600 DDR SDRAMs
Supports both 64-bit and 128-bit DDR SDRAM
Note: nForce2 does NOT supports x4 memory device. 1GB can be made by other density of dram chip such as x 8, x16.

which is the best memory to get, a matching 128 bit pair of 256 meg PC 3200 chips is what im thinking, to run in dual channel DDR,

any advantages of 64 bit instead of 128 bit memory? price difference?

 

[zShowtimez]

I belive 128 is only refering to dual channel.

 

[Lonyo]

DDR RAM is DDR RAM. The bit bit is only in reference to the pathways between the RAM slots and the CPU, to but it simply. The RAM doesn;t change.
The nForce 2 platform uses 2 64-bit memory controllers. With 1 stick of normal RAM, it has to use a single controller, so it's 64-bit RAM. With 2 sticks (if they go in the right places) both the controllers can be used (1 stick with 1 controller) so you have dual chanel (dual 64 bit channel) RAM, effectively giving 128-bits (64x2 =128).

To use both controllers you need 2 sticks of equal sized RAM (ie: 2 x 256MB sticks).
If you use 1 or 3, you only use 64-bit memory pathways, not the dual channel which gives 128-bits.
Having double the width of memory pathway theoretically doubles the memory bandwidth, but in practice, with AMD solutions, the dual channel gives little performance increasse, unless it is used with integrated graphics on the motherboard (assuming the motherboard uses nVidia's IGP northbridge).

In short, don't worry too much about it, 64 or 128 bit uses the same RAM, and doesn;t really do all that much for performance.

 

[zephyrprime]

I think you're confusing your numbers.