# PSA: Corsair LPX and AMD



## TheLostSwede (Nov 6, 2020)

I learnt something the other day from someone I know at Corsairs that's involved in their memory products.
Apparently some LPX kits are suitable for AMD use, but Corsair doesn't really mark them specifically as such on the packaging.
There is some information on their website, but the key thing to look for, is a Z in the model name, such as CMK16GX4M2*Z*5000C18.
That means the kit should work with AMD. If you get a kit without the Z in the model name, it might not work.


----------



## NoJuan999 (Nov 6, 2020)

Which explains why so many users seem to have issues running their Corsair Vengeance kits at the rated speeds on Ryzen systems.
They buy kits that don't have the "Z" in the model number.
Like a user that I just helped on another forum that has this kit: CMW16GX4M2C3600C18
He had to settle for 3200 instead of 3600 on a Ryzen 3700x rig.


----------



## INSTG8R (Nov 6, 2020)

I was wary of Corsair despite using them for over a decade on my Intel builds.  After having Mem issues initially with my Ryzen build I ended up at Vengeance Pro CL18 as my 3rd set tried 18-22-22-42. Have them easily running 16-19-19-40


----------



## Nuckles56 (Nov 6, 2020)

Huh, that's actually really good to know. It would be really good if Corsair actually publicized this fact.


----------



## 27MaD (Nov 6, 2020)

Hmmm mine are running 100% stable (check system specs).


----------



## WatEagle (Nov 6, 2020)

Also mine are stable with xmp enabled
EDIT: my model is CMK16GX4M2B23200C16


----------



## TheLostSwede (Nov 6, 2020)

Nuckles56 said:


> Huh, that's actually really good to know. It would be really good if Corsair actually publicized this fact.


Yeah, it would, but apparently they aren't. It's obvious on their website, but only if you pick a SKU that's optimised for AMD and spot the logo.
For example, this kit. However, the AMD bit doesn't show up in their search and there's no option to search specifically for AMD compatible modules.





						VENGEANCE® LPX 16GB (2 x 8GB) DDR4 DRAM 3600MHz C14 AMD Ryzen Memory Kit - Black
					

VENGEANCE LPX memory is designed for high-performance overclocking. The heatspreader is made of pure aluminum for faster heat dissipation, and the eight-layer PCB helps manage heat and provides superior overclocking headroom.




					www.corsair.com


----------



## Zach_01 (Nov 6, 2020)

My LPXs are CMK16GX4M2*Z*3466C16 (2x8GB) and XMP profile worked from day one flawlessly with any BIOS version.
I even running them today at 3800MT/s, with my little bronze rated R5 3600 on 1:1:1 ratio.
It was a lucky purchase, I didn’t know about this...


----------



## TheLostSwede (Nov 6, 2020)

Zach_01 said:


> My LPXs are CMK16GX4M2*Z*3466C16 (2x8GB) and XMP profile worked from day one flawlessly with any BIOS version.
> I even running them today at 3800MT/s, with my little bronze rated R5 3600 on 1:1:1 ratio.
> It was a lucky purchase, I didn’t know about this...


Hence the PSA, as I don't think most people are aware of this.
It's something that's easy to check without opening the packaging as well and if you buy it a shop, you can check there and then.


----------



## Nuckles56 (Nov 6, 2020)

TheLostSwede said:


> Yeah, it would, but apparently they aren't. It's obvious on their website, but only if you pick a SKU that's optimised for AMD and spot the logo.
> For example, this kit. However, the AMD bit doesn't show up in their search and there's no option to search specifically for AMD compatible modules.
> 
> 
> ...


That would have been really nice to know back in 2017 when I bought some LPX 3200 cl16 to build my brother's rig, it would have saved me much pain... I never did get that kit to run at 3200, only 2933.


----------



## xman2007 (Nov 6, 2020)

It would be interesting to know what the Z actually denotes as afaik the kits that don't work well on AMD aren't specific to a certain set of dies and some even include Samsung B-die which is generally known to work very well on Ryzen systems


----------



## TheLostSwede (Nov 7, 2020)

Nuckles56 said:


> That would have been really nice to know back in 2017 when I bought some LPX 3200 cl16 to build my brother's rig, it would have saved me much pain... I never did get that kit to run at 3200, only 2933.


Yeah, same problem I had in the past.



xman2007 said:


> It would be interesting to know what the Z actually denotes as afaik the kits that don't work well on AMD aren't specific to a certain set of dies and some even include Samsung B-die which is generally known to work very well on Ryzen systems


Sorry, no idea, he didn't go in to that much detail. At least now we know what to get and can give sound advice instead of just telling people there might be problems with LPX modules.


----------



## Caring1 (Nov 9, 2020)

xman2007 said:


> It would be interesting to know what the Z actually denotes


Zen?


----------



## NoJuan999 (Nov 24, 2020)

I just saw this kit on Newegg:
CORSAIR Vengeance LPX (AMD Ryzen Ready) 32GB (2 x 16GB) 288-Pin DDR4 3600 (PC4 28800) Desktop Memory Model CMK32GX4M2Z3600C18 - Newegg.com
It lists the "Z" kit as:

AMD Ryzen Ready
Compatible with AMD Ryzen Series CPU


----------



## tabascosauz (Nov 24, 2020)

Unfortunately, the very first kit of LPX I tried for my Ryzen is also marked AMD Ryzen Optimized on Corsair's website (CMK32GX4M2B3200C16). It only booted at 2133 with one stick. No Z, however, so that's a promising start.

There is another thing you can potentially check for Corsair if you buy a kit at a brick-and-mortar store. Look at what the Revision Number is without removing the sticks themselves from the plastic tray.

"Version Number" (reddit.com)

4.31 = Samsung, 8Gb, B-die (probably won't have trouble booting)
4.32 = Samsung, 8Gb, C-die (real bad time, can't go past 1.35V, identifies in Thaiphoon as B-die but most definitely not B-die)
5.32 = Hynix, 8Gb, probably CJR (usually boots and OCs okay with Ryzen)
5.39 = Hynix, 8Gb, probably MFR (I recall this is what mine was, probably stay tf away)

Also, some anecdotal claims that not even Revision number is a guarantee, that other dies can be found under the same number. Fun.

Honestly, this is why you should just buy something from G.skill instead. If you're able to look at the sticks in the store, their 042 code's last five digits on the sticker will actually tell you with certainty what the chips will be, to more accuracy than Thaiphoon. Also in the Reddit guide.


----------



## Sandbo (Nov 26, 2020)

That's interesting, what I followed in the past was the die used, and I got either Samsung B-die and Micron E-die, both did pretty well in general (I only really use low freq like 3200 MHz so it might not matter).


----------



## TheLostSwede (Nov 26, 2020)

tabascosauz said:


> Unfortunately, the very first kit of LPX I tried for my Ryzen is also marked AMD Ryzen Optimized on Corsair's website (CMK32GX4M2B3200C16). It only booted at 2133 with one stick. No Z, however, so that's a promising start.
> 
> There is another thing you can potentially check for Corsair if you buy a kit at a brick-and-mortar store. Look at what the Revision Number is without removing the sticks themselves from the plastic tray.
> 
> ...


I could never get my 5.32's over 3000MHz and that was touch and go. Early on, they wouldn't go over 2133MHz, but that was with a Ryzen 1700 on an X370 board, so obviously a lot of issues back then in general. They were 3200MHz modules.
Not had any problems with my Patriot Viper Steel modules that should in theory use the same ICs.


----------



## bimmerdriver (Dec 3, 2020)

First post here, also OC noob, so please excuse my questions. Also, not trying to thread-jack.

I recently bought CMK32GX4M2B3200C16 (2X16) to use with a 3400G processor in a B450M DH3H MB. The system will not boot if I select the XMP profile. Otherwise, it boots up at 2133.

I specifically ordered this memory because it was on the MB support list. I was not aware of the "Z" in the part number being for AMD, otherwise I would have chosen another kit.

According to Thaiphoon burner, the manufacturer is Nanya and the die density is 8 GB A-die, which DRAM Calculator for Ryzen does not recognize. Is this RAM equivalent to Micron A-die?

I'm wondering if I should return this RAM and order something else. It seems like a waste to have ordered 3200.


----------



## Caring1 (Dec 3, 2020)

The Ryzen5 3400G supports up to 2933MHz Ram.
I'd return it and get another set, Nanya chips aren't the best.


----------



## xu^ (Dec 3, 2020)

Mine are working fine so far, altho i did only build the machine 4 days ago  LPX 3600 *CMK16GX4M2D3600C18*


----------



## Sandbo (Dec 4, 2020)

Just want to add, this set of 16GB*2
F4-3600C16D-32GVKC
work at XMP at 3600 C16 for me with B550 and 3600X.
(tested with 8+8 hrs Karhu RAM test and Prime 95 blend)


----------



## bimmerdriver (Dec 5, 2020)

Caring1 said:


> The Ryzen5 3400G supports up to 2933MHz Ram.
> I'd return it and get another set, Nanya chips aren't the best.


Thank you for the reply. I contacted Corsair and they said it's not supported on a Ryzen, even though it's on the Gigabyte support list for the MB. I will be returning it and getting something else.


----------



## TheLostSwede (Dec 5, 2020)

Sandbo said:


> Just want to add, this set of 16GB*2
> F4-3600C16D-32GVKC
> work at XMP at 3600 C16 for me with B550 and 3600X.
> (tested with 8+8 hrs Karhu RAM test and Prime 95 blend)


Wrong thread mate. This is specifically about Corsair LPX modules.



bimmerdriver said:


> Thank you for the reply. I contacted Corsair and they said it's not supported on a Ryzen, even though it's on the Gigabyte support list for the MB. I will be returning it and getting something else.


QVL's are mostly useless imho, as they're a list of RAM that the motherboard makers have at hand, nothing more, nothing less. They don't request memory from the memory makers, although they do get sent memory from them. This is also why the QVL's are so random.
Try setting the timings and Voltage manually and they might work.


----------



## Caring1 (Dec 6, 2020)

I just bought this kit for my son's build after reading this thread a while back.
CMK16GX4M2Z3200C16
I compared to what initially seemed to be an identical kit except it had an E instead of the Z in the name.
The difference is in the details.

Memory SeriesVengeance LPXMemory TypeDDR4Memory Size16GB Kit (2 x 8GB)Tested Latency16-18-18-36Tested Voltage1.35VTested Speed3200MHzMemory ColourBlackSPD Latency16-18-18-35SPD Speed2666 MHzSPD Voltage1.2 VSpeed ratingPC4-25600 (3200MHz)

*Compared to the E version below*



*MEMORY SERIES*VENGEANCE LPX*MEMORY TYPE*DDR4*MEMORY SIZE*16GB Kit (2 x 8GB)*TESTED LATENCY*16-20-20-38*TESTED VOLTAGE*1.35V*TESTED SPEED*3200MHz*MEMORY COLOR*BLACK*SPD LATENCY*15-15-15-36*SPD SPEED*2133MHz*SPD VOLTAGE*1.2V*SPEED RATING*PC4-25600 (3200MHz)


----------



## TheLostSwede (Dec 6, 2020)

Which one is which? 
Also, do we know if the two modules uses the same brand of DRAM chips?


----------



## Caring1 (Dec 6, 2020)

TheLostSwede said:


> Which one is which?
> Also, do we know if the two modules uses the same brand of DRAM chips?


Edited to make it clearer.
I don't know if both use the same dram chips.


----------



## TheLostSwede (Dec 6, 2020)

Caring1 said:


> Edited to make it clearer.
> I don't know if both use the same dram chips.


Fair enough, at least the Z spec look much better overall. 
I presume you haven't gotten them yet?


----------



## Caring1 (Dec 6, 2020)

TheLostSwede said:


> Fair enough, at least the Z spec look much better overall.
> I presume you haven't gotten them yet?


Pick it up tomorrow


----------



## TheLostSwede (Dec 6, 2020)

Caring1 said:


> Pick it up tomorrow


It'll be interesting to see what you get.


----------



## dandaman622 (Dec 6, 2020)

Yeah you have to be careful which ones you get. On amazon there is a main page where you can go through a drop down list, and some of them will say Ryzen.


			https://www.amazon.com/Corsair-Vengeance-3200MHz-Desktop-Memory/dp/B0143UM4TC/ref=sr_1_2?dchild=1&keywords=corsair+vengeance+lpx&qid=1607258297&sr=8-2
		

Where it says style you have to make sure you choose specifically. Someone else ordered some for me and they just ordered without changing, so I got the CMK16GX4M2B3200C16. The XMP profile would crash my computer in CS GO after 5 to 10 minutes of playing. I used it at 3000mhz for a while, until I started learning a little bit and messing with timings and voltage. I eventually got it to work stable at 1.5V, but I read that raising the SOC might have helped too. I didn't get a chance to try that because I got a kit of Ballistix RGB 3200 and it's been great. Stable and easily overclocked.

Sorry for the long paragraph. Just be careful if you do decide to go with the Corsair Vengeance to pay attention to which ones you are getting like OP said.


----------



## bimmerdriver (Dec 6, 2020)

dandaman622 said:


> Yeah you have to be careful which ones you get. On amazon there is a main page where you can go through a drop down list, and some of them will say Ryzen.
> 
> 
> https://www.amazon.com/Corsair-Vengeance-3200MHz-Desktop-Memory/dp/B0143UM4TC/ref=sr_1_2?dchild=1&keywords=corsair+vengeance+lpx&qid=1607258297&sr=8-2
> ...


As I posted above, I purchased CMK32GX4M2B3200C16 and found that it will only post with XMP enabled @1.35v when the system is cold. I contacted Corsair and they told me that kit is incompatible with Ryzen. Here is Corsair's compatibility list: AMD RYZEN 2000 & 3000 SERIES Memory Compatibility List. You can see that the compatible kits have Z in the SKU. I wish I would have looked for this information before I ordered the DRAM based on Gigabyte's QVL, which is basically useless.


----------



## Caring1 (Dec 7, 2020)

TheLostSwede said:


> It'll be interesting to see what you get.


Turned out to have Nanya Dram chips and they are A die.
Not that it matters as he's one of those users that just wants it to run and doesn't tinker with the computer.


----------



## TheLostSwede (Dec 7, 2020)

Caring1 said:


> Turned out to have Nanya Dram chips and they are A die.
> Not that it matters as he's one of those users that just wants it to run and doesn't tinker with the computer.


That's highly unusual. I was expecting something like Hynix.
Again, this is so confusing with Corsair, as you never know what you get.


----------



## puma99dk| (Dec 7, 2020)

My Geil Dragon RAM isn't AMD Ryzen certifiled but they work only Asus with my current B550 board had a weird A.M.P. where it wants to run them at a 4000MHz well the Hynix kit is 3000MHz and the Samsung B-Die kit is 4400MHz if I remember correctly so there is no change that the Hynix kit will do 1000MHz OC with the same timings as the Samsung B-Die kit Asus come on I know you can do better then this 

Thank you @TheLostSwede for this, even I properly can't remember it in the future but I can try


----------



## nasky (Dec 17, 2020)

Weird mine are working fine with ryzen 3x on x570 although not marked as compatible : CMK32GX4M2E3200C16

They even overclock @3600C16 and honestly I just bought them because they were the cheapest I guess I was lucky


----------



## TheLostSwede (Dec 17, 2020)

nasky said:


> Weird mine are working fine with ryzen 3x on x570 although not marked as compatible : CMK32GX4M2E3200C16
> 
> They even overclock @3600C16 and honestly I just bought them because they were the cheapest I guess I was lucky


I think you misunderstand the point of this thread. The ones with a Z in the product name are supposed to be 100% compatible and that's why I posed the info here. 
Other LPX modules are a bit hit and miss, doesn't mean that some of them won't work, but some of them are also known to not work well with Ryzen CPUs.
You clearly got one of the good kits, but myself and several others have had kits that don't work anywhere near their rated speeds. 
Friend of mine got some with a B in the model name and although they work and are based on Samsung B-dies, they suffer from very high latency and that's with a Ryzen 7 5800X. The tRFC can't go lower than somewhere in the 500 range, which is terrible for B-dies.


----------



## nasky (Dec 17, 2020)

TheLostSwede said:


> I think you misunderstand the point of this thread. The ones with a Z in the product name are supposed to be 100% compatible and that's why I posed the info here.
> Other LPX modules are a bit hit and miss, doesn't mean that some of them won't work, but some of them are also known to not work well with Ryzen CPUs.
> You clearly got one of the good kits, but myself and several others have had kits that don't work anywhere near their rated speeds.
> Friend of mine got some with a B in the model name and although they work and are based on Samsung B-dies, they suffer from very high latency and that's with a Ryzen 7 5800X. The tRFC can't go lower than somewhere in the 500 range, which is terrible for B-dies.



yeah my tRFC too cant go below 600 but I ont think it makes that big of a difference


----------



## bimmerdriver (Dec 17, 2020)

TheLostSwede said:


> I think you misunderstand the point of this thread. The ones with a Z in the product name are supposed to be 100% compatible and that's why I posed the info here.
> Other LPX modules are a bit hit and miss, doesn't mean that some of them won't work, but some of them are also known to not work well with Ryzen CPUs.
> You clearly got one of the good kits, but myself and several others have had kits that don't work anywhere near their rated speeds.
> Friend of mine got some with a B in the model name and although they work and are based on Samsung B-dies, they suffer from very high latency and that's with a Ryzen 7 5800X. The tRFC can't go lower than somewhere in the 500 range, which is terrible for B-dies.


Here is the reply from Corsair when I asked them about this memory (without Z in the part number):

I apologize but *that kit of memory is not compatible with any Ryzen based platform* as you can see in the technical specifications listed below, and as such we do not guarantee its ability to hit the rated XMP profile.


----------



## TheLostSwede (Dec 17, 2020)

nasky said:


> yeah my tRFC too cant go below 600 but I ont think it makes that big of a difference


On Ryzen, tRFC has a huge impact on memory latency.



bimmerdriver said:


> Here is the reply from Corsair when I asked them about this memory (without Z in the part number):
> 
> I apologize but *that kit of memory is not compatible with any Ryzen based platform* as you can see in the technical specifications listed below, and as such we do not guarantee its ability to hit the rated XMP profile.


Not compatible and then not guaranteed... That's a nice answer.
Also, XMP is never guaranteed on Ryzen and is often a poor option versus setting the RAM up manually.


----------



## thesmokingman (Dec 17, 2020)

Pro tip: AVOID CORSAIR RAM LIKE THE PLAGUE.


----------



## INSTG8R (Dec 17, 2020)

thesmokingman said:


> Pro tip: AVOID CORSAIR RAM LIKE THE PLAGUE.


And yet...my RAM made the list?








						Best RAM for Ryzen 5 5600X in 2022 - Tech Edged
					

AMD Ryzen 5 5600X processor has many enthusiasts excited to build a PC around it due to its fantastic price to performance ratio. However, Ryzen




					techedged.com


----------



## Zach_01 (Dec 17, 2020)

TheLostSwede said:


> On Ryzen, tRFC has a huge impact on memory latency.


Yes it does!



thesmokingman said:


> Pro tip: AVOID CORSAIR RAM LIKE THE PLAGUE.


Well, that depends

LPX, Z series...


----------



## mtcn77 (Dec 17, 2020)

dandaman622 said:


> The XMP profile would crash my comput





bimmerdriver said:


> found that it will only post with XMP enabled @1.35v when the system is cold. I contacted Corsair and they told me that kit is incompatible with Ryzen.





puma99dk| said:


> My Geil Dragon RAM isn't AMD Ryzen certifiled but they work only Asus with my current B550 board had a weird A.M.P.





TheLostSwede said:


> XMP is never guaranteed on Ryzen and is often a poor option versus setting the RAM up manually.


XMP is Intel, AMP is AMD. I think AMD users deserve their own product placement in the memory kits'es marketing stuff. Just place an 'AMP' badge somewhere around the front of the product display and make sure to mention it means 'good for AMD'. They had the Flare X Samsung B kits that were top notch performers for both of the cpu makers that they sold out - every last kit was a B die collector's item.
They have sorted the motherboard manufacturers, they owe it to their customers to do the same with memory manufacturers.


----------



## TheoneandonlyMrK (Dec 22, 2020)

I have been very harsh on Lpx in the past but I used two Ryzen stamped kits this week and I am very happy to say that the Ryzen marked ones work well at XMP.


----------



## puma99dk| (Dec 22, 2020)

mtcn77 said:


> XMP is Intel, AMP is AMD. I think AMD users deserve their own product placement in the memory kits'es marketing stuff. Just place an 'AMP' badge somewhere around the front of the product display and make sure to mention it means 'good for AMD'. They had the Flare X Samsung B kits that were top notch performers for both of the cpu makers that they sold out - every last kit was a B die collector's item.
> They have sorted the motherboard manufacturers, they owe it to their customers to do the same with memory manufacturers.



X.M.P. is also listed at A.M.P. in a lot of AMD bios' but if you don't say X.M.P. a lot of non-tech people looks confused. I know the term just don't use it much


----------



## INSTG8R (Dec 22, 2020)

puma99dk| said:


> X.M.P. is also listed at A.M.P. in a lot of AMD bios' but if you don't say X.M.P. a lot of non-tech people looks confused. I know the term just don't use it much


It’s certainly called XMP in my Gagabyte BIOS


----------



## NoJuan999 (Dec 22, 2020)

And Asus Uses DOCP instead of XMP.


----------



## mtcn77 (Dec 22, 2020)

NoJuan999 said:


> And Asus Uses DOCP instead of XMP.
> View attachment 180617


Well, A.M.P-X.M.P variation occurs at the validation step of memory production, Asus can call it what it wants. Not to be picky about names, but for direct validation on AMD test benches before sale.


----------

