Upgrading PC3 Ram


I have a Cyber Power system that works great for me. It came with 8 gigs of PC# ram I am looking at the sets that Micro Center sells hat match my motherboard but the come in sets of two 8 gig sets, If I buy two sets would the create a problem not being a 4 module matched set?

Thanks in advance !

Best Answer

  • PowerSpec_MikeW
    PowerSpec_MikeW PowerSpec Engineer
    5 Insightfuls First Anniversary First Comment 5 Awesomes
    Answer ✓


    It doesn't need to be a four module matched kit. Match kits are mainly targeted towards overclocking. If you're pushing your memory, you're limited by the weakest module. So if you buy four of the same module individually, you could get a low binned stick and that becomes your limiter. With matched kits, all the modules are roughly equal.

    Now, you said you have 8GB, I assume that's 2x4GB. And you want to add 4x8GB to it. So lets break this down.

    Simple Answer: Try it and find out, it'll either POST or it won't. If they're not the same module, there's an element of chance here.

    Long Answer: So there's a lot of factors that go into this in regards to compatibility. Are both modules the same IC? Given the time frame, probably not, that can create issues. It's likely the 4GB modules are single sided, and the 8GB's are dual sided. Mixing those can create compatibility issues. Another factor is going to be speed. You bought a gaming PC, it's likely the memory is overclocked on an XMP profile. Adding the new RAM, you may not be able to load that speed. It'll drop to the JEDEC speed programmed on one of the kits, which is most likely a baseline for DDR3. 800 or 1066 CL11 most likely. Only option would be manual overclocking. Keep the memory where it is. Most likely A2/B2, add the new RAM to A1/B1. If you have for example an 8 and 4 in the same channel, you're operating in flex channel. 4GBx2 is dual channel, the remaining 4GB on the 8GB stick is unganged, bandwidth potential is halved.

    If it were me, I'd toss the old kit, and just run the new 16GB kit. Or grab two and max the board out.


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