[SOLVED] CAS Latency big issue for ryzen 3700x?

[Bazza23]

Hi Guys

Have just bought the following ram for my r7 3700x: https://www.amazon.co.uk/gp/product/B07D97JWDR/ref=ppx_yo_dt_b_asin_title_o01_s00?ie=UTF8&psc=1

The cas latency is worrying me but i couldn't find anything better at that speed which has a good latency. Do any of you have any suggestions as the kit i have is easily returnable or should i just stick with them? Will the latency have that much of an effect on the build?

R7 3700X
RTX 2070 Super
Gigabyte aorus elite x570

Thanks

 

[Barty1884]

To a point, yes. CL18 is pretty loose, with higher-end 3600MHz kits hitting at least CL16.

Depends on that task as to whether it's going to make a huge difference.
Realisticalyl though, I'd expect CL18 3600MHz to perform very similarly to something like CL16 3200MHz so, it's ... fine.

 

[Roland Of Gilead]

Whilst the CL is important, often at higher speeds, it's not everything. The faster mem speed balances out a little with the slower CL timing. You can experiment with changing the CL in the bios, and see if it remains stable. If so you may be able to get the DIMMS to work at CL16 and have the extra (albeit marginal performance increase). I wouldn't worry too much.

 

[logainofhades]

I use this ram, myself, due to AMD's own slide regarding ram speeds, and 1:1 ratio. That said, I doubt you will see much real world difference, between that 3600 18 and 3600 16 ram.

https://uk.pcpartpicker.com/product...16-gb-2-x-8-gb-ddr4-3733-memory-pvs416g373c7k

 

[Bazza23]

Thanks for the swift responses guys. If i could get the cl16 rated ram for similar (probably slightly more expensive) price, do you think it would be worth the hassle of returning and getting a different kit?

 

[Barty1884]

Thanks for the swift responses guys. If i could get the cl16 rated ram for similar (probably slightly more expensive) price, do you think it would be worth the hassle of returning and getting a different kit?

In very specific workloads, maybe.
But for 99% of users, no. Especially not for more money.

 

[Bazza23]

In very specific workloads, maybe.
But for 99% of users, no. Especially not for more money.

How about in regards to specifically just gaming?

 

[Barty1884]

I wouldn't say it's worth it, no.

The difference might be measurable (ie 1% lower .1% lows, or something), but it's nothing I'd worry about.

 

[Bazza23]

Thanks guys. You've eased my mind a bit. Its always a bit stressful ordering parts for a new build ^^

 

[R_1]

CAS Latency is measured in clock speeds.
you cannot compare the timings of a 3000 stick with a 3400 stick, as the frequency rises so MUST the CL. my DDR3 1600 had a CL of 8. my DDR4 3000 is rated at 16, but slow down the speeds of the RAM and the CAS will drop. the measurements are tied together.

you can only compare CL speed of RAM in the same SPEED. 3000 to 3000, 3200 to 3200, trying to compare different speeds will just be wrong as the measurement tool for each stick changes. (clock speed differences)
get the lowest CAS in the speed you need

 

[Mr.Spock]

it's measured in clock "ticks"
and you can compare timings for different speed RAM

for example CL15 @3000 yields the same true latency as CL17 @3400 - fractions are funny that way

CAS Latency is measured in clock speeds.
you cannot compare the timings of a 3000 stick with a 3400 stick, as the frequency rises so MUST the CL. my DDR3 1600 had a CL of 8. my DDR4 3000 is rated at 16, but slow down the speeds of the RAM and the CAS will drop. the measurements are tied together.

you can only compare CL speed of RAM in the same SPEED. 3000 to 3000, 3200 to 3200, trying to compare different speeds will just be wrong as the measurement tool for each stick changes. (clock speed differences)
get the lowest CAS in the speed you need