RAM Speeds

[philthedonald]

Hey there,

I'm currently contemplating whether or not to buy the Nova 15,6 with an AMD Ryzen 3700x.
As far as I can see, other OEMs do support the laptop with up to 3200 MHZ RAM. But according to the8auer on YouTube, the 3200 MHZ Ram from Corsair is only CL22.

Now pcspecialist only offers 2666MHZ RAM, but as it's the same Clevo chassis, the 3200 should also work for this laptop.
But the 2666 Ram from pcspecialist is CL18 (as far as I can tell, not sure about this one). Would I benefit of buying the laptop with the cheapes RAM config (4GB RAM) and just swapping that stick out with two 3200 mhz cl22 ram sticks or are two 2666 sticks at cl18 actually better?

I don't exactly understand what CL means, only that the8auer was not a big fan of it and swapped it out immediately.
Hope anyone can help me out with this.

ps: Does anyone know if the Displayport out on the Nova 15,6 supports G-sync? Already contacted support about it, but haven't gotten an answer yet.

 

[ubuysa]

CAS latency (CL) is basically how many clock cycles it takes for the RAM chip to output the data from the requested address. Thus lower CL numbers are better. In general and assuming transfer rates are the same.

This might help: https://www.crucial.com/articles/about-memory/difference-between-speed-and-latency

 

[Scott]

The CAS Latency is a product of the frequency so you ideally need to calculate it out to see what the actual latency would be in total. If the CAS is really low and there's not a lot in the frequency then there may be a benefit. More often than not when the numbers are closer it is better to favour frequency. In your cases:

22/3200*2000 = 13.75ns
18/2666*2000 = 13.5ns

This would favour the 2666 RAM.

 

[philthedonald]

Thanks that helped me out a lot!

Also for anyone wondering:
I've heard back from pcspecialist and the DP ports in both machines do support G-Sync. Might be nice to know.