[SOLVED] Question about memory compability

partiesplayin

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Nov 20, 2013
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Hey there guys wondering if you can answer a lingering questions for me .

I've been building computers for myself for years, and I always check the motherboard's manufacture website for ram compatibility . But I have lingering questions I've never really seen or read the answer to .

So I'm assuming the compatibility list is Strictly ram that the manufacture has tested and deemed qualified as compatible .

My question is what makes the ram incompatible , if it falls under the speed requirements for a given cpu, motherboard combo .

For example a motherboard supports DDR4
4266(O.C.)/4133(O.C.)/4000(O.C.)/3866(O.C.)/3800(O.C.)/3733(O.C.)/3600(O.C.)/3466(O.C.)/3400(O.C.)/3333(O.C.)/3300(O.C.)/3200(O.C.)/3000(O.C.)/2933/2800/2666/2400/2133 MHz ram speeds
what would make 1 mem chip differ from another combability wise given it meets the above requirements . I'm not talking about mixing and matching sticks.

I'm talking about if I choose ram not on the combability list but it meets the above requirements what might make it incompatible with a particular motherboard . i was thinking about throwing together a workstation on x299 platform but i cant find any of the ram on the combability list . Well maybe some but boy that rgb stuff looks nice :)
 
Solution
Hey there guys wondering if you can answer a lingering questions for me .

I've been building computers for myself for years, and I always check the motherboard's manufacture website for ram compatibility . But I have lingering questions I've never really seen or read the answer to .

So I'm assuming the compatibility list is Strictly ram that the manufacture has tested and deemed qualified as compatible .

My question is what makes the ram incompatible , if it falls under the speed requirements for a given cpu, motherboard combo .

For example a motherboard supports DDR4...
A lot of variables come into play related to timings, voltages, specific chips, etc

You can be sure that the motherboard manufacturer has NOT tried all possible RAM combinations to come up with that compatibility list.

So the list on the website will never be complete. A lot of RAM not listed will work fine.

I'd try to buy something on the list, but that may not be possible depending on your situation.

An alternative is to go to Crucial's web site and use their compatibility tool. It is quite accurate if you are willing to buy Crucial brand RAM.

I would specifically try to avoid adding new RAM to old RAM. That's really asking for trouble and it's very hard to know if it might work. You can get lucky or very unlucky. Buy all you need in one purchase...a matched kit.
 
Hey there guys wondering if you can answer a lingering questions for me .

I've been building computers for myself for years, and I always check the motherboard's manufacture website for ram compatibility . But I have lingering questions I've never really seen or read the answer to .

So I'm assuming the compatibility list is Strictly ram that the manufacture has tested and deemed qualified as compatible .

My question is what makes the ram incompatible , if it falls under the speed requirements for a given cpu, motherboard combo .

For example a motherboard supports DDR4
4266(O.C.)/4133(O.C.)/4000(O.C.)/3866(O.C.)/3800(O.C.)/3733(O.C.)/3600(O.C.)/3466(O.C.)/3400(O.C.)/3333(O.C.)/3300(O.C.)/3200(O.C.)/3000(O.C.)/2933/2800/2666/2400/2133 MHz ram speeds
what would make 1 mem chip differ from another combability wise given it meets the above requirements . I'm not talking about mixing and matching sticks.

I'm talking about if I choose ram not on the combability list but it meets the above requirements what might make it incompatible with a particular motherboard . i was thinking about throwing together a workstation on x299 platform but i cant find any of the ram on the combability list . Well maybe some but boy that rgb stuff looks nice :)

"So I'm assuming the compatibility list is Strictly ram that the manufacture has tested and deemed qualified as compatible ." Correct.

"My question is what makes the ram incompatible , if it falls under the speed requirements for a given cpu, motherboard combo .
Mixing RAM especially from differing manufacturers or with differing frequencies or CAS Latency. A mismatch/fail can occur if the frequency of the RAM is beyond the IMC capability or the MB.

"what would make 1 mem chip differ from another combability wise given it meets the above requirements"
DIMMs are binned at the factory after manufacture into kits. It is the density/Latency of the Silicon in the chips that determines compatibility.

When choosing a RAM kit, it is best to select from the MB QVL to ensure they are tested and known to work with the MB. You can choose outside the QVL however you may have a frustrating time getting things stable if you don't know what your doing and best to keep within JDEC standards.
 
Solution