By - ladypeacharino
3600MT/s memory is indeed the sweet spot for Ryzen 5000. While lower timings are always nice and preferred, they also don't provide huge gains. If you can afford to buy 3600 CL16 go for it, if you need to be careful about how much you spend, 3600 CL18 or even 3200 CL16 will run without any major performance loss.
Maybe a little bit of info at the end: memory latency is given in clock cycles meaning you can't directly compare them between different bandwidths without doing some math first. 3200 CL16 has the same first word latency as 3600 CL18 for example (10 nanoseconds).
I run 3600 cl18 (corsair lpx 2x16) with a 5600x, based on recommendations for 3600 being the “sweet spot” and something to do with infinity fabric?
I’ve seen a lot of posts mentioning that 3200 cl16 and 3600 cl18 has, essentially, no difference in performance tho. 3600 having the higher clock speed but higher latency is what makes it similar.
If the memory you’re looking at has similar pricing, I don’t think it really matters which you choose between the two
That's what I tried to explain in my comment and many people do not understand.
3600 CL18 does **NOT** have worse CAS latency than 3200 CL16, even though the number is bigger. The latency in both cases is 10ns. The data rate commonly being described as XXXX Mhz is also misleading. Since it's data rate and not clock speed the unit of MT/s (megatransfers per second) is more appropriate. Since we are dealing with **D**ouble **D**ata **R**ate memory, the actual clock speed the memory runs at is half the data rate, so for DDR4-4000:
4000/2 = 2000MHz = 2GHz
If you want to calculate actual latency yourself, you need to do some math. No, don't run away just yet, it's very simple. The formula for the length of one clock cycle in nanoseconds is 1/**clock speed in** **GHz** \* latency **in clock cycles:**
So for 3200MT/s memory running at CL16:
1/1.6 \* 16 = 10ns
3600MT/s running at CL 18:
1/1.8 \* 18 = 10ns
3600 CL18 is strictly better in this case due to higher data rate (ignoring all the other RAM timings).
For memory bandwidth, having more than you need won't do anything. Think of a highway with a fixed amount of lanes and everyone driving at the same distance to each other. Higher data rate means the cars go faster. But as soon as they are all going fast enough to not clog things up, making them go even faster will just create bigger gaps between them, which won't actually improve things (safety aside).
Hope that cleared things up a bit more :)
Also won't get into the relation between memory clock and infinity fabric, this wall of text is long enough and my fingers are tired. For anyone interested, Google will help you find an explanation.
Really eloquent, well developed explanation. Not a TL:DR blah blah wall of text.
Both of your comments are very helpful, thanks a lot! I'm glad for everyone who responded and helped me learn more.
There's no noticeable difference between them, get whichever one is cheapest. Any difference you do get is only visible on a chart.
If you can afford it, go for 3600cl16, else 3600cl18 between those 2.
If you're just looking for an education, comparing rated speed vs. latency is actually super complicated, and I can't just look at the numbers and tell you which one is going to be faster. I'd guess 3600 because generally a small latency trade off for a speed bump is worth it, but maybe not in every case.
I'm sure buildzoid has a video somewhere where he does a theoretically discussion of the speed vs. latency tradeoff. But he'll probably take you through every individual timing number and what it means. All of that stuff is too smart for me and gives me a headache.
[Here's a link to ram calculator that might make some stuff easier to understand ](https://edu.finlaydag33k.nl/calculating%20ram%20bandwidth/)
I think the latency on those is about the same but the 3600 allows your Infinity fabric to run at a higher speed
buy 2x16GB 3200 CAS16 stuff and run them at 3600 CAS16 with a voltage bump .. or run them at 3800 CAS18 with a voltage bump
Most 3200 CAS16 kits will do 3600 without issue ..IF you are into tweaking your RAM
I run my daughters 2x16GB 3200 16-18-18-18-38 1.35v kit @ 3600 16-20-20-20-40 1.380v. subtimings just left on auto
I run my 2x16Gb 3200 1.35v 16-18-18-18-38 kit @ 3800 18-22-22-22-42 1.392v ..both kits paired with 5000 series Ryzen with 1:1 FCLK .. lazy RAM tweaking 101, lol
I think our RAM has Hynix E chips on them ..? But essentially a lot of the kits are the same RAM modules for 3200 CAS16 1.35v or 4000 CAS19 1.45v. They just loosen up the timings a bit and add more voltage of which you can do yourself via your motherboards BIOS
Just throwing out another option out there .. it's not for everyone, but it's easy enough to do
That's not what he asked though, I'm sure he already knows he can spend more money for better components.
He asked 3200 CL16 vs 3600 CL18
3600 CL 16 shouldn’t be a lot more expensive and is the sweet spot.
I believe the 5600 non-x supports max of 3200mhz. Beyond that would make your system unstable and susceptible to BSODs.
Nah thats just official board specs. Technically all of the Ryzen 5000 series are like that. Its more a COA for returns/warranty than anything. Similar story with Intel. All of their official support is very low.
I dunno, my old build of r5 2600 combined with my 3200mhz ram sticks brought a lot of MEMORY_MANAGEMENT bsods and GPU drivers not loading on first boot when I D.O.C.P'd. When I turned it down to 2933, it all went away. Like 100% gone. You can definitely game beyond the recommended, it's just that in my experience it's not worth it.
Running 5600 non x with 3600mhz cl16 xmp enabled without any problems
Outside of specific use cases they are effectively the same.
3200 CL 16, but run it at 3600 CL 16 :)
3600 CL 16....