[SOLVED] Serial numbers in RAM

[Guru X]

Hey there,i have a SK Hynix HMT351U6AFR8C-H9 and i was looking for one identical stick of RAM.
As i only have a few bucks,i prefer not buying the dual channel kit even though it would be preferable in most cases.
So which key letters do i have to look for in Hynix RAMs for dual channel compatibility.

For those who do not understand, i meant ,that which of the letters in the Serial Number(HMT351U6AFR8C-H9) actually matter or MUST match.

For example i found out that 'A' in the serial letter does not really matter too much.....

I am attaching a file link for Hynix RAM lettering guide :
https://www.skhynix.com/static/filedata/fileDownload.do?seq=190

 

[kanewolf]

Hey there,i have a SK Hynix HMT351U6AFR8C-H9 and i was looking for one identical stick of RAM.
As i only have a few bucks,i prefer not buying the dual channel kit even though it would be preferable in most cases.
So which key letters do i have to look for in Hynix RAMs for dual channel compatibility.

For those who do not understand, i meant ,that which of the letters in the Serial Number(HMT351U6AFR8C-H9) actually matter or MUST match.

For example i found out that 'A' in the serial letter does not really matter too much.....

I am attaching a file link for Hynix RAM lettering guide :
https://www.skhynix.com/static/filedata/fileDownload.do?seq=190

Unknown. Matched pairs are TESTED by the manufacturer for use as a set. You are trying to do the same thing the manufacturer did when they had 1000s of DIMMs to match. You have two. Maybe it will work, maybe not. The only guaranteed purchase is a matched set.

 

[extreme_noob]

Not completely sure what you're asking here, but you don't have to pick apart serial numbers to get a kit that works in dual channel. As long as they are the same capacity, same frequency, and roughly the same or similar timings, it will work fine in dual channel. (if they're off by a little, the motherboard generally does a good job of syncing them up to the looser set, though it wont always work)

As an aside, the "A" is part of "AFR" which is mostly what people refer to that Hynix die as. It's actually the most important determining die, as it is what identifies the revisions of dies Hynix did. DJR scales better, and can be binned higher than CJR, which is better than AFR, and so on. The serial number also doesn't determine bin, since that's generally done by manufacturers like G.skill and Corsair, even though bin is perhaps the most important for finding a kit that will work in dual channel.

 

[CountMike]

http://www.softnology.biz/files.html can tell you all you need to know about your RAM modules.

 

[Guru X]

Not completely sure what you're asking here, but you don't have to pick apart serial numbers to get a kit that works in dual channel. As long as they are the same capacity, same frequency, and roughly the same or similar timings, it will work fine in dual channel. (if they're off by a little, the motherboard generally does a good job of syncing them up to the looser set, though it wont always work)

As an aside, the "A" is part of "AFR" which is mostly what people refer to that Hynix die as. It's actually the most important determining die, as it is what identifies the revisions of dies Hynix did. DJR scales better, and can be binned higher than CJR, which is better than AFR, and so on. The serial number also doesn't determine bin, since that's generally done by manufacturers like G.skill and Corsair, even though bin is perhaps the most important for finding a kit that will work in dual channel.

Well,i meant,can i get another identical stick by looking at certain parts in the serial number?(Hynix)

 

[extreme_noob]

Well,i meant,can i get another identical stick by looking at certain parts in the serial number?(Hynix)

As I said in the original message: The serial number also doesn't determine bin, since that's generally done by manufacturers like G.skill and Corsair, even though bin is perhaps the most important for finding a kit that will work in dual channel.

 

[captaincharisma]

Well,i meant,can i get another identical stick by looking at certain parts in the serial number?(Hynix)

i'm curious how you would plan to buy ram based soley on serial numbers given if this was a fesable option ?

would you keep buying and returning ram sticks from a place like amazon until you find the serial number you wanted? or would you go into a store and endlessly look through boxes of ram sticks to find a match?

that would be looking for a needle in a haystack

 

[Karadjgne]

Ram is a bunch of silicon ic's on a pcb, regardless of the heatsink which is just a piece of painted tin glued to the outside.

That Silicon is unique. During its manufacturing process almost all impurities are spun out, but some remain. Could be gold or silver or lead or iron, carbon or any number of other minerals or metals in any combination.

All of the IC's on that sheet of silicon are a batch and share the same properties when it comes to electrical transfer. They stand a good chance of being compatible with another stick from the same batch.

What you generally see is the Primary timings, that's the 16-16-16-39 printed on the label. What you don't see is the 40+ Secondary and Tertiary timings that are affected by the impurities in the silicon. Get a couple of those out of sync and the stick stands a chance of incompatibility.

Doesn't matter if it's identical ram, from the same store, bought on the same day, from the same shelf, from the same box, that arrived from the same manufacturer in the same shipping container. It's different.

I've had Corsair ram that was identical in every way, only 9 production numbers apart, total failure of compatibility because one stick was close to the end of one batch, and the other stick was close to the beginning of the next.

I've also had ram that was different in every way. Different speeds, timings, vendors, OEMs, even voltages, that when paired worked like a champ. No adjustments necessary.

Mixing ram is pot-luck. It either works, works with adjustments or fails. There's no way to predict or even stack the deck in your favor since even consecutive production serial number sticks can be incompatible. Best option is always to buy the full amount you want in a single kit because it's already been stacked in your favor to be compatible by the factory, you mixing means you become the testor and try to find compatible IC impurities out of the Billions of IC's produced every year.

That's looking for 1 particular needle out of a billion needles in a billion haystacks.

 

[SamirD]

Since this is just plain jane ddr3, I would just find another one with the exact same part number and you should be good. There's nothing to gain price-wise for 'similar' part numbers so just get the same one and you should be fine.