Can you mix ddr3 ram sizes?


I’ve recently posted a thread about advice on a new computer and I’m close to making my purchase. However there is one subject I’m a bit confused on, even more so after trying to google the answer as there is conflicting statements everywhere. My question is, when upgrading ram of the ddr3 variety can you do so independent of size? Meaning if I have a single stick of say a 6GB ddr3 can I upgrade by installing a 4GB stick into the open slot or does the memory have to be paired in size? Can I only upgrade with another 6GB memory stick or do I have the flexibility to install a 2GB, 4GB or more? Thanks

You can plug in any combination of sizes motherboard supports. However, a lot of computers have dual-channel memory interfaces, which gives you a small performance increase from using “matched sticks”. The difference is pretty modest for most ordinary users. Some memory bandwidth limited tasks may run 5-10% faster, but for most purposes the difference is trivial or nonexistent.

Also, AFAIK there aren’t any 6 GB sticks. Only 2, 4, 8, etc sizes.

You can mix up different sizes, but it’s not recommended. For example, a dual channel 2x2gb 1600mhz pair of sticks will be faster than 5gb 1600mhz of 2+2+1 sticks.

In theory you can; in practice, PCs can behave very oddly if you do. You should try to have matching banks of memory (e.g. 2x 4GB and 2x 8 GB). If you have different DIMMs - and that includes being of the same capacity but of different speeds - ensure they are in different banks, even if it means leaving an empty slot.