Possible Duplicate:
Are there any benefits to using identical memory modules?

I have a pair of mismatched RAM sticks in my laptop (slots 3 & 4 in the following image):

I have a matching Micron stick, but getting at the Hyundai to replace it is going to be a pain (unlike the other 3 slots, this one requires removing ~30 screws and the screen to get at, my laptop is Asus G53SW).

I've been told pairing RAM from different manufacturers can cause problems. Is this true, or should I just leave the mismatched pair as is?

marked as duplicate by studiohack Feb 6 '12 at 16:29

This question has been asked before and already has an answer. If those answers do not fully address your question, please ask a new question.

  • Memory is so cheap, why not just buy a matched set for 3 and 4 that match 1 and 2? – Moab Feb 3 '12 at 22:33
  • 2
    What program did you use to get the info? – kinokijuf Feb 6 '12 at 16:20

Unless you're having problems, the answer is no. Timings and such can be important if you're looking at a high performance system, and timings can be more similar and closely matched with matched sets of memory. But for a "normal" system, there's no need to match memory.

  • Also, as it happens, his timings and voltages match almost perfectly. – David Schwartz Feb 3 '12 at 23:04
  • thanks. just to clarify, given that I have two pairs of RAM, I assume this means it's wise to match the pairs with each other as well (eg 4 sticks of micron)? – jela Feb 4 '12 at 22:52
  • 1
    Even matching similar things is ly required if you're setting up a high performance system. Seeing as the g53sw is a performance system, matching timings can be good if you're planning to overclock or looking to squeeze the last nth of performance out of the hardware. I would recommend researching memory timing and performance tuning and determine what you truly want and/or need. – music2myear Feb 5 '12 at 15:06

I've been told pairing RAM from different manufacturers can cause problems. Is this true, or should I just leave the mismatched pair as is?

Yes, it's true. But you're not having problems, so why change things?

Having a computer can cause problems. Should you get rid of your computer?

  • I am not sure under what circumstances problems would arise. Presumably a poorly overclocked system might also operate normally most of the time. – jela Feb 4 '12 at 22:55
  • Every system should be stress-tested after any change to memory hardware or timings, definitely. memtest86+ is the best too for that job. – David Schwartz Feb 5 '12 at 0:57

Mismatched RAM may, but won't necessarily cause issues. If removing one of the modules is so much hassle, I'd say make sure that you have a good backup (just in case if something goes wrong) and try using the laptop for some time with the 4 sticks the way they are. If you see more issues than before (e.g. crashes, BSOD), it is likely that they are caused by the mismatched RAM. In that case, use matched modules. If everything is fine, just keep the RAM as it is.

Keep in mind that some of RAM module manufacturers use chips from other manufacturers. Also, even if the modules are from the same manufacturer, they should ideally be from the same batch (buying in pairs makes this quite likely).

  • The actual chips are nearly always made by another manufacturer (Fujistu, Micron, Samsung, NEC, Panasonic, Toshiba, et al..). – paradroid Feb 3 '12 at 23:27

I'll echo the other suggestions that if you're not having problems with the RAM, there is no need to worry about mismatched sticks.

That said, some of the issues with using different RAM is:

  1. If your system supports dual or triple channel, it will likely not use that unless both the RAM sticks happen to have exactly same timings
  2. The entire memory subsystem will run at the speed of the slowest stick (so if one is DDR3 1600 and other 3 are 2000 MHz, those are also going to run at 1600 instead)

Greatly Mismatched memory will kill interleaving thus effectively halving bandwidth for bulk transfers (like multiport 10GbE network, or enormous games of today) Even if it does not disable interleaving and modules get detected correctly, they will work at slowest speed (hopefully) Maybe you tell your computer type and we can tell which hyunday and which micron is a match for your corsair? Plain module timings are different, so there is a slim chance everything breaks.

  • 3
    Mismatched vendors won't kill interleaving. Mismatched sizes would, but that doesn't seem to be the case here. – Ben Voigt Feb 4 '12 at 1:45

Not the answer you're looking for? Browse other questions tagged or ask your own question.