Large capacity DIMM recommendation for Ryzen 3950X and Crosshair VIII Hero

fatfurrycat · 10 Apr 2020 at 16:21

Hi All,

I'm just in the process of building a new system based on the Ryzen 3950X and Crosshair VIII Hero.
It's going to be used for a variety of tasks, including gaming, rendering and virtualisation.

I initially ordered the 32GB (4x8GB) 3600Mhz 8Pack Xtreem CL16-16-16-36 kit.

This seemed to be the best RAM size and performance compromise that I could find in the UK. There do seem to be faster kits available elsewhere, but none I could find here.

However, I've just taken on a new project, which is going to require a minimum of 64GB.
I'm now in a bit of a quandry as to which RAM to go for. At the moment, I've ordered the Corsair Vengeance LPX 2x32GB 3600 MHz CL18-22-22-42 kit. I'm wondering if I should perhaps have gone for the Vengeance RBG Pro, which is the same price currently.

Does anyone know what ICs are actually used on these two types of DIMM? I've read that some of the lower clock speed kits actually have Samsung modules, but that these higher speed DIMMs might either be Micron or Hynix. I've also read that having 4 x DIMMs from the LPX range can be problematic (which might be a consideration in the future if I need to go beyond 64GB).

Would really appreciate people's thoughts, or suggestions of alternatives at a similar price point.

Thanks,

Andy.

Bluntwrapped · 11 Apr 2020 at 11:33

Used Samsung ECC UDIMM could also be an option.

There’s a few B die UDIMM 16GB sticks in here:

https://www.samsung.com/semiconduct...esource/2018/06/DDR4_Product_guide_May.18.pdf

Seem to overclock quite nicely going by what others are saying.

EsaT · 11 Apr 2020 at 12:32

Samsung has had 16Gb chips for long time, but those have gone to server/workstation memories.
10/something nm A-dies have such bigger capacities.
"Good old" overclocker favourite 20nm B-die is limited to 8Gb chips and 16GB per (dual rank) DIMM.
Also there are 32Gb chips, including Micron.

Anyway no matter the chip maker proper BIOS support for these might be spotty on desktop platform.
Threadripper has no doubt priority for tuning AGESA for high capacity DIMMs.
Especially considering how many are reluctant to recommend 2x16GB claiming that 2x8GB is enough.
(but have no problems paying bat crazy GPU overprices for no future proofness)

Could have gone for clearly cheaper board.
Already proper £200 boards have overkill VRMs for any AM4 CPU.
Also chipset cooler design quality of Asus is from Athlon era 15 years ago without chances for semi passive operation.

fatfurrycat · 11 Apr 2020 at 16:07

Thanks for the responses. Much appreciated.

I've tried looking at the list of ECC memory, but the speed in 32GB DIMMs seems to be limited to 2666MHz.
I'm guessing they might overclock to 3200MHz, but 3600MHz might be a stretch?
The prices on eBay don't seem to be any cheaper than going with the 2x32GB kit that I've already ordered.

It's beginning to look like I'll either have to compromise on the speed, or on the overclocking ability.
There doesn't seem to be a happy medium in a 32GB DIMM at the moment.
The new Crucial Ballistix 2x32GB CL16 kit looks good, but I can't find any stock currently, which is a shame.

I guess the other alternative is to go with a 4x16GB 8-Pack kit, but that limits my future upgrade options and is pretty damned expensive.

If anyone has direct experience of either the LPX or Vengeance RGB Pro with overclocking, then I'd appreciate your feedback.
From what I can find, they both use Hynix chips, so are unlikely to go much beyond their rated frequency/timings.

fatfurrycat · 11 Apr 2020 at 23:27

Turns out that the Vengeance LPX and Vengeance RGB Pro are both using a new Hynix CMR die.
Things like Ryzen DRAM calculator haven't been updated to include it yet.

There's some reasonable info on it here:
https://forum.corsair.com/forums/showthread.php?t=192599
and here (in German, so you'll need to translate it):
https://www.hardwareluxx.de/index.p...g-a-die-erste-eindruecke-der-16-gbit-ics.html

The long and short is that it doesn't seem to overclock very well, and it can be a challenge to make it run well if you have 4 DIMMs.
From what I'm reading, the 3600MHz kit won't go past 3200MHz on most boards if you have 4 DIMMs.

I'm trying to decide if it's worth cancelling the order, and going with the way more expensive 4x16GB 8Pack Xtreem kit.
I'm not likely to need more than 64GB, so this is one possiblity for me. It's whether I can stomach the extra £140.

Quartz · 11 Apr 2020 at 23:52

fatfurrycat said:
However, I've just taken on a new project, which is going to require a minimum of 64GB.

My basket at Overclockers UK:

1 x Corsair Vengeance RGB Pro 128GB (4x32GB) DDR4 PC4-29200C18 3600MHz Quad Channel Kit= £689.99

Total: £698.69 (includes shipping: £8.70)

Go big or go home.

fatfurrycat · 14 Apr 2020 at 09:29

Quartz said:
My basket at Overclockers UK:

1 x Corsair Vengeance RGB Pro 128GB (4x32GB) DDR4 PC4-29200C18 3600MHz Quad Channel Kit= £689.99

Total: £698.69 (includes shipping: £8.70)

Go big or go home.

No stock, though.

LeMson · 15 Apr 2020 at 08:00

If your using that much ram you prolly want a quad channel platform not duel, try a thread ripper build

So you can go bigger capacity etc

fatfurrycat · 15 Apr 2020 at 11:33

LeMson said:
If your using that much ram you prolly want a quad channel platform not duel, try a thread ripper build

So you can go bigger capacity etc

In these current times, I simply can't afford to go threadripper.
The 3950X offers me the best compromise between cores and cost. I doubt I'll ever need more than 128GB during the lifetime of the system I've just built.
If I do, hopefully the economic situation will have improved, so building a bigger system won't be as much of an issue as it is now.

8 Pack · 16 Apr 2020 at 14:49

The 3600 16x4 64gb kit is working totally fine in this boar as is 3600mhz 8x4 32gb. The corsair 3200mhz 32gbx2 or two kits of this also working fine. On 3xxxX ryzen cpus mem frequency not as important as previous gens for performance...

The ecc stuff won't overclocks... We tried all this stuff out before..

fatfurrycat · 16 Apr 2020 at 15:17

8 Pack said:
The 3600 16x4 64gb kit is working totally fine in this boar as is 3600mhz 8x4 32gb. The corsair 3200mhz 32gbx2 or two kits of this also working fine. On 3xxxX ryzen cpus mem frequency not as important as previous gens for performance...

The ecc stuff won't overclocks... We tried all this stuff out before..

Thanks for the confirmation on the 16x4 kit.
I'm currently just running with just 2x8GB 8-Pack DIMMs, which work great. Didn't see the point in using the other two, as I know they will be going back.
With regards to the 64GB configuration, then I wanted to have just two DIMMs, so that I have room for upgrade in the future.
Would hate to spend £500 on the 4x16GB 8-Pack config only to sell them for a massive discount when I need to upgrade.

The Vengeance RGB Pro 2x32GB kit should be here tomorrow, so I'll be able to do some comparison benchmarks on the OOTB bandwidth and latency with the 8Pack B-Die.
I know it won't be as good, but I suspect it will be good enough.

I'm sure that more options for 32GB DIMMs will come to market once the current crisis is over. I'm just going with what I can get right now.
From what I'm reading, these Hynix CMR dies don't overclock very well, but I might get lucky. I can but try.

If you've got any thoughts on the best way forward with them, then I'd appreciate any feedback. The Ryzen DRAM calculator doesn't support them yet, so I'm not totally sure how to proceed.

Thanks again,

Andy.

8 Pack · 16 Apr 2020 at 15:35

My feedback would be who cares about not even 1%... Just run and have fun.... 3200mhz is enough and it works without hastle on such capacity dimms.