NON LR post (computers)

[Pedro_The_Swift]

Is DUAL channel memory a marketing tool?
I'm all for LOTS of memory,, but
what happens when you have say,
2X1gb sticks and want to add a third?
or
more commonly
2X512 sticks
?

as lots of boards can now take up to 8gb its becoming increasing harder($$) to keep adding TWO modules each time

any ideas?
theories?
white papers?

[spudboy]

You only have to add them in pairs if you want the dual channel double data rate (DDR) to work. You can add any combination of DIMMs to any slot, but you lose the dual channel advantage.

If the memory module pairs are not the same density (i.e. capacity) then the dual channel won't work, so you need matched pairs.

Your motherboard manual will say what the valid combinations of slots/chips are.

[spudboy]

Also - forgot to point out that dual channel motherboards will not have an odd number of slots, so if your motherboard only has 3 slots then it won't be a dual channel MB.

[incisor]

some dual channel boards do have only 3 slots.....

they switch from syncronous to asyncronous mode if ram is mismatched...

and some will treat the third stick as paged cache....

[spudboy]

Well there you go - I stand corrected! All of ours are colour coded 4 socket, so just assumed you needed pairs.

[Pedro_The_Swift]

they switch from syncronous to asyncronous mode if ram is mismatched...



and this is a bad thing?

How much performance loss?

[incisor]

hardly visble to the naked eye in my experience..