Question about RAM compatibility with a Ryzen 9 5950 X

[lectorramnoobie]

Good evening, I have a PC to do 3D rendering , for photo, video and encoding and game , (Msi MEG x570 Unify, Ryzen 9 5950X and Rtx 3090) but when buying and assembling the PC I skip Quality ram for lack of sufficient budget. After a few months overtime I find myself with a good budget to change my RAM, but I have some problems understanding the infinity Fabric.

Currently I have 64 GB of DDR4 3200 mh Cl 16 and my FLCK is at 1900 MHZ on the BIOS.

However, I found a pack of 64 GB 3600 mhz CL 14 (14-14-14-34) Or CL 14 (14-15-15-35) and I would like to know if at the level of the infinity fabric it's okay pass or if I will have stability problems

I admit to being a bit lost and not having much Ram knowledge with AMD processors, so if in addition to your answer there is an explanation of why, that would be perfect.

(English is not my first language, so I apologize for mistakes and grammar)

 

[lowrider_05]

if you run your IF @1900 and your Ram @3200, you loose performance, your IF should be half of the Ram, so for Ram@3200->IF@1600

for the other part, if you can run your CPU stable @ up to 1900 Mhz IF, then the 1800 Mhz IF for the desired 3600 Mhz Ram should also be possible.

But to be shure you should check the RAM QVL of your motherboard to see if the desired Ram Kit will work.

 

[lectorramnoobie]

Thank you for your answer,
my motherboard accepts RAM up to 4600/5000+ Mhz by JEDEC and A-XMP OC MODE, Being in Cl 14 won't require more infinity fabric than being in CL 16?

Here are the 2 RAM kits that could interest me, knowing that I will end up putting 64 GB

ALTERNATE - Le spécialiste en ligne High-Tech&!

PC personnalisés, portables, gaming gear et plus, achetez-les chez ALTERNATE.

www.alternate.fr

G.Skill 32 GB DDR4-3600 Kit, Memory
(White, F4-3600C14D-32GTZN, Trident Z Neo) (Cl 14 15 15 35 ) and

https://www.alternate.fr/G-Skill/Tr...odule-de-m%E9moire-32-Go-2-x-16-Go-DDR4-3600- MHz/html/product/1754086?partner=FrIdealo&campaign=DDR4/G.Skill/1754086

G.Skill Trident Z Neo F4-3600C14D-32GTZNA 32GB 2 x 16GB DDR4 3600MHz memory module

CL 14-14-14-34

Will I have much difference between the CL 14-15-15-35 and the CL 14-14-14-34?

 

[Chomiq]

Welcome to TPU.

First of all, fill out your system specs under:

https://www.techpowerup.com/forums/account/specs

What's your current memory kit (brand, SKU - model number)? Maybe it would be better just to tune it instead of spending €600+ on new memory kit.

Like @lowrider_05 said, you should run your MEM Clock (half of your ram speed) with 1:1:1 ratio for FCLK and UCLK. Which means that when running your current 3200 MT/s kit your FCLK should be set to 1600 and UCLK should also be set to 1600.

 

[lectorramnoobie]

Welcome to TPU.

First of all, fill out your system specs under:

https://www.techpowerup.com/forums/account/specs

What's your current memory kit (brand, SKU - model number)? Maybe it would be better just to tune it instead of spending €600+ on new memory kit.

Like @lowrider_05 said, you should run your MEM Clock (half of your ram speed) with 1:1:1 ratio for FCLK and UCLK. Which means that when running your current 3200 MT/s kit your FCLK should be set to 1600 and UCLK should also be set to 1600.

I just did it ! and the Ram is Ballistix Black 32 GB (2 x 16 GB) DDR4 3200 MHz CL16 BL2K16G32C16U4B (64 GB 4*16)

 

[lowrider_05]

Thank you for your answer,
my motherboard accepts RAM up to 4600/5000+ Mhz by JEDEC and A-XMP OC MODE, Being in Cl 14 won't require more infinity fabric than being in CL 16?

Here are the 2 RAM kits that could interest me, knowing that I will end up putting 64 GB

ALTERNATE - Le spécialiste en ligne High-Tech&!

PC personnalisés, portables, gaming gear et plus, achetez-les chez ALTERNATE.

www.alternate.fr

G.Skill 32 GB DDR4-3600 Kit, Memory
(White, F4-3600C14D-32GTZN, Trident Z Neo) (Cl 14 15 15 35 ) and

https://www.alternate.fr/G-Skill/Tr...odule-de-m%E9moire-32-Go-2-x-16-Go-DDR4-3600- MHz/html/product/1754086?partner=FrIdealo&campaign=DDR4/G.Skill/1754086

G.Skill Trident Z Neo F4-3600C14D-32GTZNA 32GB 2 x 16GB DDR4 3600MHz memory module

CL 14-14-14-34

Will I have much difference between the CL 14-15-15-35 and the CL 14-14-14-34?

I also would suggest, you read the following Guide/Article to see what Ryzen does with different Memory Types/Speeds and what gains are to be expected:
https://www.techpowerup.com/review/amd-ryzen-memory-tweaking-overclocking-guide/

 

[lectorramnoobie]

I also would suggest, you read the following Guide/Article to see what Ryzen does with different Memory Types/Speeds and what gains are to be expected:
https://www.techpowerup.com/review/amd-ryzen-memory-tweaking-overclocking-guide/

It's quite hard to understand and I think I have to read it several times but I do have a good idea of what it gives,

I also know given the quality of my current ram that I could not necessarily overclock it or my research for better RAM

I can't find / Understand what impact the CL can have on the amount of infinity fabric needed for RAM or whether with 64 GB 1900 Mhz (For DDR4 3600) will be stable

 

[Taraquin]

If you plan to tighten up sub timings, go for at 3600cl14 kit, if you plan on run xmp may aswell get a 3600cl16 kit as performance difference will be extremely small. Most gains come from subs.

 

[lectorramnoobie]

Yes i plan to tighten up sub timings

if you run your IF @1900 and your Ram @3200, you loose performance, your IF should be half of the Ram, so for Ram@3200->IF@1600

for the other part, if you can run your CPU stable @ up to 1900 Mhz IF, then the 1800 Mhz IF for the desired 3600 Mhz Ram should also be possible.

But to be shure you should check the RAM QVL of your motherboard to see if the desired Ram Kit will work.

I just tried to lower my IF from 1900 to 1600 and I did a test on the same game in benchMark, in 1900 I had an average of 125 Fps and the biggest drop was 17 while at 1600 I have an average of 123 Fps but a drop of 35, is this normal behavior?

 

[oobymach]

the IF should be 1:2 with your ram so if you have 1600 IF you need 3200 ram, for 3600mhz ram you need 1800fclk or your ram will be slower. Also 1900fclk is unstable for most people but if you have no crashes or issues with stability testing (P95 etc) you need ram at 3800mhz for 1900fclk.