Latency

[Goonie Lifer]

When looking at ram, i always hear that 3600 is better to have compared to 3200.  But when you add latency in your choice of ram, is a lower latency in a 3200 better than a higher latency in a 3600 when it comes to speed or operation?  What is it when it comes to latency?  Is it a deal breaker to you if your choice of ram comes with a high latency? 

[Eigenvektor]

In general, lower latency is better. The thing is that latency is usually given in clock cycles, so for example CAS 16 @ 3200 MHz (=10 nanoseconds) and CAS 18 @ 3600 (=10 nanoseconds) is exactly the same.

[Goonie Lifer]

If i choose 3600 ram, does having CAS 18 noticeable if its compared to CAS 16 or even lower in game play?  Or in your opinion, does it really matter to you in your decision when choosing ram?

[Bombastinator]

4 minutes ago, Goonie Lifer said:

If i choose 3600 ram, does having CAS 18 noticeable if its compared to CAS 16 or even lower in game play?  Or in your opinion, does it really matter to you in your decision when choosing ram?

My understanding is that for ryzen it does more than intel.  I’ve seen charts that imply the difference is “large” I don’t know how big “large” is in this case though.  There are videos by several you tubers on it.  Iirc Linus did one but there are several.

[Eigenvektor]

Just now, Goonie Lifer said:

If i choose 3600 ram, does having CAS 18 noticeable if its compared to CAS 16 or even lower in game play?  Or in your opinion, does it really matter to you in your decision when choosing ram?

It's usually not very noticeable (a few FPS at best). Anything between 16-18 should be perfectly fine. I usually try to find some balance between speed, latency, size and price. E.g. get as much RAM as I need, get the speed that I want and then get the lowest latency that is still affordable.

 

To be clear, both lower latency and higher clocks are "better". So in general you want the highest clocks and the lowest latency. Both have diminishing returns and both start to get very pricey at the high end. Which one is more important depends on the software you're using. Is it more sensitive to latency or transfer speed?

 

You can search YouTube, there are e.g. several videos by JayzTwoCents, Paulshardware etc. on the topic with benchmarks of some games. Example: