Memory Speed

[diajohn 164]

I am close to a new build for flight simming but wonder what, if any, effect memory speed has on the sim.  My guess is little but really don;t know.  This will be with an Intel Z390 chipset.

 

Thanks

[lownslo 590]

This is a test using FSX from 3 years ago but nevertheless shows the importance of memory speed in building a balanced system for simming:

And in this recent thread, note Avsim member "FunknNasty" posting screenshots of his 8600K running at 5.2GHz... his AIDA64 Memory performance is most impressive! 

The end result is that his well tuned hardware and OS work in balance to yield great performance... specifically a minimum of stuttering and textures that don't wait to load until he flies by.  You're planning on a Z390 build, and I can assure you that it could perform well... just be sure to define a balanced system before you start the build.  Go for the fastest CPU + fastest GPU + fastest memory + fastest motherboard your budget allows.  Put it all together with a well tuned OS and sim, and you'll really enjoy the experience.

Good luck and HTH,

Greg

[Bob Scott 7,704]

Balance is the key.  Putting expensive fast memory on a stock or mildly overclocked CPU won't help much, and putting skunky slow consumer-grade bottom-bin RAM on a highly overclocked 6/8 core machine will leave some of that expensive CPU performance you paid for on the table, because the CPU will be idling (but very fast) while it waits through extra clock cycles for data from memory.

Memory true latency is the primary metric--the time (in nanoseconds) it takes from when a read/write request is made until data is available on the bus.  DDR true latency is calculated by multiplying the CAS latency by 2000, then dividing that by the memory frequency in MHz.  So 2133 MHz CAS 14 RAM would have a true latency of (2000 x 14) / 2133 = 13.13 ns and 3600 MHz CAS 15 RAM would have a true latency of (2000 x 15) / 3600 = 8.33ns. 

Lower latency is better.  Currently ~8.25ns is near the cutting edge of fast, extreme performance, ~9ns is performance-level, 10ns is average, and above 10ns is slow consumer-grade stuff.

When you buy memory, frequency is only part of the equation...lots of companies are selling high-frequency RAM with ugly high CAS latency to unsophisticated buyers that don't understand this simple math.  Caveat Emptor.

Regards

[fghdgdfdfgfgf 111]

talkin memory but showing off new cpu ...yeah, memory is funny like that ...

 

...it's an 8086

[fghdgdfdfgfgf 111]

On 1/18/2019 at 8:43 AM, w6kd said:

When you buy memory, frequency is only part of the equation...lots of companies are selling high-frequency RAM with ugly high CAS latency to unsophisticated buyers that don't understand this simple math.  Caveat Emptor.

Regards

Oh, and they 'may' be selling over rated or mislabeled "hi-speed" "low cas" ram to 'sophisticated' buyers also ...

[shally17 1]

Thanks