Splitting a Dual Channel Pair

[makwy2]

If I purchase a dual channel pair of DDR3 sticks will there be any performance problem if I split that pair across two difference computers?

I want to take a pair of 2gb DDR3-1333 sticks and put them into different machines. The first will go into the 3rd slot of a computer that already has 2x2gb in it, the other stick will be the only stick running a re-built machine running XP.

Is this ok? will this cause problems?

 

[hellwig]

There's no problem splitting the pair up, they aren't tied to each other in any way.

The problem MIGHT occur when placing one of the sticks into a computer that already has 2x2GB in it. You want to make sure that the voltages that each stick requires are the same. You don't want to overvolt any of the sticks, but undervolting might work, still best to avoid it though.

You also want to make sure the timings for all the sticks are close enough, otherwise, performance could take a hit. This is less of an issue, I'm running a computer with mismatched dimms just fine, it runs 24/7.

The best bet would be to buy another set of whatever is already in the first machine.

However, I wonder why you need 6GB in one machine? If that machine is currently running in dual-channel mode, adding the third stick will drop it out of dual-channel (unless its running an x58 chipset and you want to run triple-channel, then I understand). Are you doing some heavy computations and need more memory? Are you running a 64-bit OS so you can actually use that memory?

 

[makwy2]

Thanks for your quick response. Let me answer those questions and give some info here.

1st the Machine with 2x2gb that I am adding the 2gb stick to, let's call it machine A, has a 2x2gb set of DDR3-1600 (1.65V) currently running at DDR3-1333 (1.5V). The NEW pair is actually clocked at DDR3-1333 (1.65V).

All timings are at 9-9-9 so I doubt timings will clash.

Yes, I am running 64-bit Win7 and my board can handle up to 16gb.

The reason I am adding the 2gb stick is because I was looking to get 2gb for the re-built Machine B and I just thought to myself "hmm... why don't you just get the marginally more expensive 4gb set and add some to Machine A!"

I haven't bought it yet and though I'd ask here before I take the plunge.

 

[hellwig]

Short answer: No, there won't be any problems doing what you want to do.

Long answer:

Since they're all rated at 1.65 it shouldn't be a problem (you might have to use 1.65 to keep the second set at DDR3-1333). Just remember you''ll drop machine A from dual-channel to single-channel.

To be honest, I don't know if you'll see a performance boost of any kind. You'll have 2GB more memory, but you might not need it in the first place. Plus, single-channel might slow down the machine a bit, but I'm not sure you'd notice that either.

Basically, you'd probably see more performance keeping the 4GB together in machine B then moving half of it to machine A (even if B uses a 32-bit OS, it will see 3+ GB). If you do things that require a lot of memory (CAD design, modelling, etc..), then it could be worth it to Machine A, otherwise, you might just save yourself whatever marginal cost we're talking about.

 

[makwy2]

hmm you've given me a lot to think about... Thanks, hellwig!

 

[makwy2]

Best answer selected by makwy2.