ROG STRIX X670E-E problem with 4 dimm DDR5-6400

[Manu0x01]

I buy 4 DIMM to get 128GB DDR5 at 6400, but only works with 2 DIMMs. If I put 4 dimm the system don’t boot and show me an error.

I have to Disable D.O.C.P. To get and stable system but a get only 3600MHZ 😰

This a issue? The memory are 2x32GB 6400Mhz TeamGroup T-Create. I buy 2 kits to get the 4 DDR5.

the main reason to buy this motherboard was to get a 128GB DDR5-6400 working as they say in the technical spech

[Murph_9000]

Assuming you mean the Strix X670E-E, your memory is not on the Strix X670E-E Gaming Wifi Memory QVL for a 4 DIMM config.  The tech specs refer you to the memory support list; they do not say you can use any DDR5 memory in a 4x32GB configuration.  The "socket support" column must be "1,2,4" for 4 DIMM configs; "1,2" indicates only 2 DIMM configs are validated/tested as working.  Keep in mind that all XMP/DOCP/EXPO memory speeds and timings are overclocked and not guaranteed to just work in every case.

There are no 6400 MT/s DIMMs validated for use on any X670E boards as a 4 DIMM config, in general.  You can't use the fastest RAM for 4 DIMM configs.  You have to choose between speed in a 2 DIMM config or capacity in a 4 DIMM config, you can't have both the highest speed and the highest capacity (this has always been the case, as was the same for DDR4).

There are no Team Group DIMMs validated for 4 DIMM configs at any speed.  This could indicate that there's a problem with their DIMMs running in a 4 DIMM config, or it could be that they have just not yet tested them for that.

There is only one model of 32GB DIMM validated as a 4 DIMM config, and that's a Kingston DDR5-4800 part.  The other 4 DIMM configs on the QVL are all for 4x8 and 4x16, up to a maximum speed of 5600 MT/s.

It's possible that more 4x32 configs will be added to the QVL in the future, but unlikely that there will be a 4x32 DDR5-6400 config for X670 any time soon on any board.

[feanor_black]

This means that the manufacturer needs to clearly write that the motherboard does not support 128 GB of RAM and does not guarantee their operation in 99% of cases on most configurations at the declared frequencies, and this is just a kind of hidden deception of buyers when in the technical description the possible is presented as valid and stable

[Murph_9000]

The tech specs don't say that 4x32 highly overclocked is a valid configuration.  They refer you to the QVL.  It's a DDR5 problem, 4x32 overclocked is a problem on all boards, as the DDR5 silicon just isn't good enough to do that at the moment (and some of it is the memory controllers on the CPUs as well).

[feanor_black]

Already after the purchase on overclock.net, I met a non-isolated case when all 128 GB work for people without any problems at a frequency of 5600, and on reddit there are even cases when all 4 modules work stably at 6000 ..... and unfortunately this not on asus motherboards, but on competing motherboards from MSI and Asrok, which suggests that other motherboard manufacturers can provide 4 modules at a frequency of 4800+, but alas, asus cannot, although it is a more common brand relative to competitors. Regarding my X670E Hero motherboard, I’ll say even more - on the later 1416 and 1516 BIOSes, it became almost impossible to run 4 modules at a frequency above 3600, which is surprising, because in the early version 0805 ... 1303 I could, although with difficulty, achieve 4800 .. .. Moreover, I took from a colleague at work his motherboard asrock X670E taichi carrra, where I inserted my processor and a set of 4 memory and on auto-tuning on the last BIOS booted to 5200 with a voltage of 1.1, and I see that the HERO simply does not know how , it is loaded on the car only at 3600 and that's it, but for 4800 you need to unscrew the voltage on the modules up to 1.35, and what conclusion should I draw? 😉 ...... until I change the HERO purely because of the large number of type-c ports on the rear panel, which taiichi carra simply does not have, but they are more important to me for working with high-speed external drives and I hope that in new ASUS bios will improve support for 4x32 GB at least to the level of their other motherboard manufacturers.

[Silent_Scone]

I've 192GB working on the Strix @ 5200, although a reasonable CPU Fabric is needed.

[feanor_black]

I willingly believe you, but I want it to work for all people everywhere - right out of the box and without problems, and not just for the moderator from the ROG site, who probably has access to selected pieces of equipment 😉

[Silent_Scone]

 

Memory density support comes down to AMD ucode. The latest AGESA revision now supports 48GB DIMMs. However, overclocking is never guaranteed, and for users with some knowledge gaps the QVL serves some guidance.

[Manu0x01]

This is bad news, because ASUS must "Warning" about this issue to know first... not when we configure the MB and the configuration don't work. The difference between this two configs are HUGE!... on 6400Mhz (2x32GB) the speed is 72GB/s but in the default configuration (4x32GB) at 3600 the speed is 48GB/s... and the all point to buy FAST and EXPENSIVE memories is to use at full speed... not the lower, because in that case i can buy another memory (cheaper) to get 128GB at maximum speed.

i feel very disappointed 😞

[Murph_9000]

It's not really anything new.  It was just the same for DDR4, highly overclocked 4x32 DDR4 does not work.  As DDR4 matured, 4x32 with a small overclock was possible; it might improve a little as DDR5 silicon matures, but is unlikely to ever work at the highest overclock speeds.  The warning is on all the spec sheets to check the memory support list.

The synthetic benchmark numbers are huge, but the actual difference it makes to most normal workloads can be very small.