Impact of mixing memory chips in dual channel config?

I've got a current system with a 2 GB matched pair of Corsair DDR2 CM2x1024-6400C4 (2.1 volt, v2.1) running fast and stable in dual channel configuration.

I intend to upgrade my system one last time and have been searching for an additional similar pair of memory. I've found a few, but I'm confused which one would be the better pick.

Option a) what looks like the exact similar version of memory chips, v2.1, however unsure if it is a 'matched pair'. Offered quite expensive.

Option b) a confirmed 'matched pair', however v6.2. Offered very cheap.

Looking at the version information in this forum, it seems v6.2 uses different memory chips compared to v2.1 (64Mx8 PROMOS compared to 128Mx8 PSC).

If I were to avoid any risk, I'd obviously go with option a), however I'm not sure if this is really necessary. Hoping anyone can advise me.

Thanks

Rene

combining more than 1 package of ram is not supported or suggested.

that being said your most likely compatibility would be of the same version although its still without any guaranty they will work together at all.

if you want a 4 gig kit you should buy a single kit of 4 gig. this way they have already been matched at the factory and you will have full support if you need help with timings or other settings.

its up to you but if you add ram there is no telling what will happen.

combining more than 1 package of ram is not supported or suggested.

that being said your most likely compatibility would be of the same version although its still without any guaranty they will work together at all.

 

if you want a 4 gig kit you should buy a single kit of 4 gig. this way they have already been matched at the factory and you will have full support if you need help with timings or other settings.

 

its up to you but if you add ram there is no telling what will happen.

What he said! :p:::pirate::

Thanks for the replies guys. The PDF was a good read. Note I couldn't read the page that the left link pointed to.

I'm left with a question though: what's the worst that can happen if you "add" memory? Will it not work at all? Will there be memory errors? Or would I simply be limited to using less aggressive settings?

As to buying new memory modules, if I were to consider 2nd hand, eg 2x2GB: do you guys have tips of identifying matched pairs other that asking if it is a matched pair and trusting the seller?

I'm left with a question though: what's the worst that can happen if you "add" memory? Will it not work at all? Will there be memory errors? Or would I simply be limited to using less aggressive settings?

Could be all of the above including data corruption would be another one. Then there is always the chance they run just fine. All you can do is physically try it. We can't predict what WILL happen , just give you a heads up on what could happen .

As to buying new memory modules, if I were to consider 2nd hand, eg 2x2GB: do you guys have tips of identifying matched pairs other that asking if it is a matched pair and trusting the seller?

There is no way to tell those either , unless serial numbers are close. But even then SN's may not be sequential due to the way they are tested. I wouldn't buy them second hand just because you have no warranty if they are bad.