memory Ryzen 9 5900x with 4x8 32GB 3200mhz or 2x8 16GB of 3600mhz (both DDR4)

[Nicholas_65]

(this is on the ASUS TUF X570 board) 

Well I've been eyeing at Ram lately and i was wondering if it would be better to get a HyperX Fury 4x8 32GB Kit at 3200mhz C16 Or a Corsair Vengeance Pro 2x8 16GB kit but at 3600mhz C18 would it make any difference at all? If so what kit would you recommend?

[Chris Pratt]

For a 5900X, yes it makes a big difference. It's a multiple CCD design, so you need somewhere in the neighborhood of 3600-4000MHz for the FCLK (infinity fabric clock) to be able to run as high as possible. If you go with 3200MHz, you're leaving significant performance on the table.

 

Additionally, it's better to have just two sticks of RAM than four, as four puts more stress on the IMC. Dual channel platforms aren't really intended to have more than two slots. Manufacturers add four because there's a nonsensical notion among consumers that it's preferable so they can "upgrade" the RAM later by adding additional sticks. In practice, that's almost always a bad idea, as it's next to impossible to match existing sticks years down the line, and the result will often be instability or inability to run at the full rated speed.

 

There is some value in having four ranks, which would require four sticks of single rank RAM to achieve. However, you can get there with just two sticks of dual rank, as well, so that would be the preferable path.

 

The capacity is inconsequential, as long as you have enough for the workloads you're throwing at the rig. For gaming, 16GB is more than sufficient. Depending on the type of productivity work you, 32GB may be necessary. However, again, even if you do need 32GB, I'd get a kit of 2x16GB 3600MHz CL16 dual rank before anything else.

 

[Levent]

Ranks? Can you post the product codes of the RAMs in question?

[freeagent]

Runs just fine with 4 sticks. Not sure why people say it’s so stressful on the IMC. 4 single ranked sticks is no problem. I can’t comment on a higher ranked setup as I have not run one on AM4 yet. 

[Nicholas_65]

On 1/12/2022 at 9:54 AM, Chris Pratt said:

For a 5900X, yes it makes a big difference. It's a multiple CCD design, so you need somewhere in the neighborhood of 3600-4000MHz for the FCLK (infinity fabric clock) to be able to run as high as possible. If you go with 3200MHz, you're leaving significant performance on the table.

 

Additionally, it's better to have just two sticks of RAM than four, as four puts more stress on the IMC. Dual channel platforms aren't really intended to have more than two slots. Manufacturers add four because there's a nonsensical notion among consumers that it's preferable so they can "upgrade" the RAM later by adding additional sticks. In practice, that's almost always a bad idea, as it's next to impossible to match existing sticks years down the line, and the result will often be instability or inability to run at the full rated speed.

 

There is some value in having four ranks, which would require four sticks of single rank RAM to achieve. However, you can get there with just two sticks of dual rank, as well, so that would be the preferable path.

 

The capacity is inconsequential, as long as you have enough for the workloads you're throwing at the rig. For gaming, 16GB is more than sufficient. Depending on the type of productivity work you, 32GB may be necessary. However, again, even if you do need 32GB, I'd get a kit of 2x16GB 3600MHz CL16 dual rank before anything else.

 

Thanks alot for the help, Very informative!