Duel Channel Memory question.

[catattack]

Hey guys. What if I got 2 Corsaid 256mb memory in duel channel... would it matter if I put a crappy 512mb stick in another slot?

[catattack]

Corsair*

[Trickle]

It would be a case of 'weakest link' scenario. All 3 memory sticks will only run as fast as the slowest stick. Same applies to memory timings aswell - buy a cheap stick that can only do Cas2.5 and all three will have to run at cas2.5

In addition, there is the chance that the mobo isnt good handling 3 sticks and running 3 sticks together will force you to run lesser timings overall than you would have to for the weakest stick on its own. Finally, you get the odd scenario where certain boards simply dont like certain types of memory and using all 3 slots together attenuates the issue and you can get system instability or simply not work at all.

tbh, running at stock frequencies and low timings, pretty much all boards will work with 3 slots on 95% of memory out there.

[Wolf Man]

I personally never mix RAM, so keep the same manufactorer and same speed RAM etc.

[catattack]

So, if my board is NF7-S and I've always been using one crappy generic 512mb stick and I am gona get two 256mb Corsair ddr 2700 in duel memory. Will that increase its performance by a little, some, or a lot?

[Austin]

I would suggest buying a stick which matches as closely as possible. You would want to ensure the 2x256MB are on 1 channel while the 1x512MB is on the other as that is most likely to give the better perf. However AFAIK no nForce2 mobo can operate at 400mhz (DDR400 / PC3200) with all 3 RAM slots filled so you may have to back down much closer to 333FSB (PC2700). I doubt you'll see much impact on perf outside of sythetic benchmarks but you may want to consider selling your current 2x256MB (which there's still loads of demand for) and grabbing 2x512MB instead. That will save you a lot of potential headaches. No need for Corsair at all, any good brand of PC3200 is more than fine, Crucial or TwinMOS are my favourites while Adata are also gaining serious aclaim.

[Austin]

Sorry. So you have 1x512MB (?) of crappy RAM (PC3200/2700?) and are wondering what you'd get from 2x256MB Corsair PC2700?

Well if you are happy with 333FSB (seems strange since your mobo and cheap CPUs are happy at 400FSB) then PC2700 is all you need (although PC3200 costs little more).

You get optimal perf by using Dual Channel which req's 2 sticks (or more) of RAM. That's good for a 5% speed boost on its own. It's not fully known what perf impact running with all 3 slots filled in various configurations on various nForce2 is but 2 sticks is certainly more ideal.

Any decently branded PC3200 is way better than Corsair's PC2700 so do consider how much you're paying. I would seriously rec using 2 sticks of PC3200, 512MB (2x256MB) is still not limiting for almost all home users. Weigh up the costs and make your choice...