Why is this DDR4 RAM only compatible with Intel ?

Barometer

Limp Gawd
Joined
Mar 25, 2012
Messages
150
SKU CMK16GX4M2A2400C16
VENGEANCE® LPX 16GB (2 x 8GB) DDR4 DRAM 2400MHz C16 Memory Kit - Black



Some say it makes no difference...other say it does? I can't get a solid answer. Corsair says it's compatible with certain INTEL systems, not AMD4 systems. . WHY?
In fact, seems most Corsair memory says it's only Compatible with certain Intel systems?

My Mainboard is an ASRock AB350M Pro4 and has XMP capability and recognizes the RAM, But I currently have an AMD A10-9700 CPU....changing to a Ryzen 7 2700X next week.

This was taken directly from the Corsair Tech Support Website

Fan Included
No
Memory Configuration
Dual / Quad Channel
Memory Series
VENGEANCE LPX
Memory Type
DDR4
Memory Size
16GB Kit (2 x 8GB)
Tested Latency
16-16-16-39
Tested Voltage
1.2V
Tested Speed
2400MHz
Memory Color
BLACK
SPD Latency
16-16-16-39
SPD Speed
2400MHz
SPD Voltage
1.2V
Speed Rating
PC4-19200 (2400MHz)
Compatibility - Intel 100 Series,Intel 200 Series,Intel 300 Series,Intel X299
Heat Spreader
Anodized Aluminum
Package Memory Format
DIMM
Performance Profile
XMP 2.0
Package Memory Pin
288
 
Last edited:

GiGaBiTe

Gawd
Joined
Apr 26, 2013
Messages
988
Without knowing the P/N of the memory ICs on the memory modules, I can only speculate it's because they used low density memory ICs vs high density.

There exists two common types of memory ICs, high density and low density. The difference between the two is how the bits are laid out in rows and columns on the memory die. High density has narrower rows and more columns while low density has wider rows and fewer columns.

Further complicating things is the same descriptions can be used for overall memory chip capacity. So an example is you could have a 2 gbit module using four 512 kbit chips (high density) or eight 256 kbit chips (low density).

The way memory is laid out is important because Intel memory controllers have historically been extremely picky about what type of memory it will work with. In most cases, Intel wants low density memory or it will complain or not work at all.

AMD on the other hand has historically not given a flying toss about what kind of memory you have in the system, as long as it's memory. 3rd party chipsets are even more lax. Got a stick of ECC, a stick of registered and a stick of unbuffered? toss them all together, it won't care. It just won't use the more advanced memory features.

tl;dr, that memory will work fine on any AMD platform that supports DDR4
 

cyklondx

Limp Gawd
Joined
Mar 19, 2018
Messages
415
Its mainly referring to XMP 2.0, and timings. The amd is unable to read (correct me, as i'm likely wrong) whole xmp data array. I think amd is only reading first 176 bytes of data, while intel tends to read up to 255 bytes. Thus not all timings are being read on amd platform.

Compatibility only refers to systems corsair has tested it on.

They will work on AMD system without issues, just the XMP profiles may require tinkering before they work at advertised Hz. (thought thats the case for most sticks anyway, even on intel platforms)

Another things, a blasts from the past. Where AMD didn't have ddr4 cpu's, and only intel had ddr4 support.
 

IdiotInCharge

[H]ardForum Junkie
Joined
Jun 13, 2003
Messages
13,238
It's mostly because AMD half-assed their memory controllers and their board partners half-assed UEFI support for memory on the market.

Most of this has been figured out on later board revisions and with Zen 2 / Ryzen 3000, however, you're going to want to get as detailed of a workup as you can as to what timings the memory is supposed to run at beforehand. You'll want that information ready when you first post the system, before you go installing operating systems and so on. Get those set and Memtest it first.
 

Rvenger

[H]ard|Gawd
Joined
Sep 12, 2012
Messages
1,952
It's mostly because AMD half-assed their memory controllers and their board partners half-assed UEFI support for memory on the market.

Really? Thats not true. AMD's memory controller was totally fine. It was the damn Asmedia chipset boards and AGESA that AMD botched. Zen 1 couldn't reach 3200mhz OC in most cases unless you had Samsung B Die but they did hit their target speeds of 2666mhz and OC up to 3000mhz on Zen 1 with a proper AGESA.
 

Master_shake_

[H]ardForum Junkie
Joined
Apr 9, 2012
Messages
10,682
you know how i look up memory?

does it fit and is it fast.

haven't had a misstep yet.
 

IdiotInCharge

[H]ardForum Junkie
Joined
Jun 13, 2003
Messages
13,238
Really? Thats not true. AMD's memory controller was totally fine. It was the damn Asmedia chipset boards and AGESA that AMD botched. Zen 1 couldn't reach 3200mhz OC in most cases unless you had Samsung B Die but they did hit their target speeds of 2666mhz and OC up to 3000mhz on Zen 1 with a proper AGESA.
The memory controller is on the CPU. The ASMedia chipset is just that -- it's not related to memory. The AGESA code is written by AMD.

The whole memory controller implementation on Zen 1 was ass. Zen+ fixed a little of that with speeds and compatibility going up, but only now with Zen 2 and the latest UEFI updates is memory compatibility approaching what we've had on Intel for a decade.
 

Rvenger

[H]ard|Gawd
Joined
Sep 12, 2012
Messages
1,952
Cool story. Kyle mentioned the memory controller being robust. But your the expert on everything AMD even though you don't own a single AMD CPU ...so hey. Keep up the good work buddy!!!



To the OP. Don't worry about the RAM. You should not have any issues. You may need to play with timings a little but it will work out. Just update the BIOS to the latest version.
 
Top