DDR 2 Ram & dual channel

[potkettleblack]

Just want to clear something up before I possibly pour money down the drain....

I am getting a new bare bones system, Core 2 Duo etc etc. It comes with 1gb (2 sticks of 512mb) of dual channel DDR2 667mhz PC5400 240pin RAM.

Am I right in thinking that with "dual channel" I have to add additional sticks of 512mb in order to increase the overall amount of RAM? Whereas if I was to buy an additional single stick of 1gb then the mobo wouldn't recognise it? Also do they need to be in pairs of 512mb?

The mobo has 4 DIMM sockets so I guess I can get it up to 2gb in total by grabbing another couple of 512mb sticks of RAM although it seems to me to make more sense to put in sticks of 1gb or 2gb rather than the 512mb so I can get the best out of it. But then that means literally binning the 1gb it will come with which seems a waste of money.

Cheers in advance.

[spannersatcx]

In order to use Dual Channel Memory, your motherboard has to be capable of supporting this technique and you will also need two equal memory modules.

Best to check with the motherboard manufacturer.

You fit it in pairs normally the first pair would be fitted in slots 1 & 3, second in slots 2 & 4, most manufacturers actually colour the slots so you can't mix them up.

You would have to check with your motherboard manufacturer to see what you can and can't do. It is possible that the 2nd pair you put in could be 1GB each, it's the pair that needs to be matched, not all 4.

My advice would be if you feel the need to get 2GB's of RAM don't mess with 4x 512mb sticks just get 2x 1GB to start with, as filling all 4 slots with relatively small sticks means that should you feel the need to get more RAM then you will be removing perfectly good sticks which is a waste of money.

[Mac the Knife]

If it comes with 2 matched sticks of 512MB and you want to go to 2GB I'd suggest just getting another two identical sticks of 512MB rather than binning them and getting two new 1GB sticks. Unless you're running a webserver there's not much point in going over 2GB even with Vista :yuk:

Even Linux, which uses memory more intensively than Windows (for speed and efficiency) won't ordinarily benefit much from > 2GB

But be careful, fast dual-channel setups are quite sensitive to minor variations in memory timings so be sure that the sticks are matched.

Many, many systems are unstable not because of the OS or duff drivers but because memory modules are not properly matched or timings are set too aggressively in the BIOS. Your system must be able to run Memtest86 - http://www.memtest86.com/ - overnight without errors or it will never be stable.