RAM Speed advice/info

[JediMonsoon]

I have ordered a build that includes the

Processor (CPU)
AMD Ryzen 9 5900X 12 Core CPU (3.7GHz-4.8GHz/70MB CACHE/AM4)

and

Memory (RAM)
32GB Corsair VENGEANCE RGB PRO DDR4 3200MHz (2 x 16GB)

I have seen various posts that say that the best speed to have for Ryzen is 3600MHz but I have also seen others that say due to the timing difference the 3200MHz is the same speed. I'm just wondering what the true answer is as the difference in price is not loads and so just wondering whether I should upgrade my order?

Any advice is appreciated.

 

[NoddyPirate]

Just some interesting reading:

5000 series RAM Guide

"DDR4-3200 is still the officially supported memory frequency on Ryzen 5000." - "Our test results confirmed that DDR4-3600 is still the sweet spot for this generation, though."

I find it nigh on impossible to tell what Latency you will get with PCS RAM, but the 3600 MHz seem to be CL18 while 3200 MHz is CL16 generally as far as I can tell. This gives identical true latency - ((CL divided by MHz) by 2000)) between the two - but the 3600 MHz would still be expected to peform better overall due to the higher bandwidth and the higher FCLK that the faster RAM requires - (Ryzen FCLK must be 1:1 with the base Memory Clock - i.e. 3600Mhz / 2 for Double Data Rate RAM)

As for a 'true' answer? Not sure if one really exists!

 

[JediMonsoon]

Just some interesting reading:

5000 series RAM Guide

"DDR4-3200 is still the officially supported memory frequency on Ryzen 5000." - "Our test results confirmed that DDR4-3600 is still the sweet spot for this generation, though."

I find it night on impossible to tell what Latency you will get with PCS RAM, but the 3600 MHz seem to be CL18 while 3200 MHz is CL16 generally as far as I can tell. This gives identical true latency - ((CL divided by MHz) by 2000)) between the two - but the 3600 MHz would still be expected to peform better overall due to the higher bandwidth and the higher FCLK that the faster RAM requires - (Ryzen FCLK must be 1:1 with the base Memory Clock - i.e. 3600Mhz / 2 for Double Data Rate RAM)

As for a 'true' answer? Not sure if one really exists!

Thank you @NoddyPirate it is indeed interesting reading! I will certainly take it all into consideration. Does Corsair RAM have the option to be bought at specific Latency or is it just thats what he different frequency come as? Sorry if I sound foolish in these questions as I'm still learning about all these things, though loving it as I go!

 

[NoddyPirate]

Does Corsair RAM have the option to be bought at specific Latency or is it just thats what he different frequency come as? Sorry if I sound foolish in these questions as I'm still learning about all these things, though loving it as I go!

Not foolish at all - there is no such thing as a silly question!

You can buy Corsair Vengeance 3600 MHz with 14, 16 or 18 Latencies as far as I know, obviously with CL14 being the most expensive but it seems (again just my impression from what I've seen here) that the latter is what you get from PCS. Hopefully some others here that actually have received that RAM might be able to give you more accurate info.

Alternatively - and probably best actually - you can ask PCS themselves. If you do - please report back here for the rest of us aswell!

 

[DarTon]

I bought a machine from PCS in April. It was an AMD 5900X with 2x16GB Corsair Vengence 3600MHz, non-RGB memory. It's timings were 18-22-22-42.

I started off speccing it with 3200MHz CL16 on basis that 3200/16 = 3600/18 and it was £38 cheaper to go with the 3200 (cheapskate I am). Did some research that implied 3600 was the marginal sweet spot but it wasn't exactly a major deal. Opinions on this forum seemed to favour 3600. I changed my order to 3600.

I've found I can move the timings down to CL16 without any issues. I wasn't brave enough to try CL15 or CL14, and I've put it back to CL18 to be honest.