Ram memory Timing

[WildThane]

Can some one explain what the Timing does and what is the number combination represents, example- Timing: 14-14-14-34 or Timing: 16-18-18-38... ?

 

[Soulkeeper]

they are clock cycles needed to perform certain actions
lower is better

overall latency of your memory is a combination of frequency and clock timings

 

[BonzaiDuck]

He's got that right. You can wiki some string like "memory latency timing" and learn more than we present here.

There is a sequence of steps which occur in discrete clock-cycles necessary to perform a memory operation or operations of various kinds.

These are all obviously measured in integer clock-cycles.

Column Access Strobe or tCAS -- generally, the first number, most significant in comparing memory timing specs.

Row Access Strobe or tRAS -- I believe this is the last of the four basic timing numbers.

tRP -- Row Pre-charge

tRCD -- RAS to CAS delay

I'm doing this from the top of my head, don't remember all the specifics or remember them incorrectly. And candidly, I can't remember if the last two items mentioned are either 2nd or 3rd respectively.

Generally, given the state of the technology and the simplest implications, the higher the speed, the looser (larger) the timings or latencies.

For some memory makes, you could look at their spec pages for two models of the same model lines but of different speeds. They could give you an indication as to where to start if you want to overclock your own RAM instead of buying that of higher speed. So if I see a set of DDR3-1600 with 9-9-9-24, I might be able to run them at DDR3-1866 and 10-10-10-30.

And I can only opine that following short-cuts like that will save you time to learn or apply even more specific information and doing integer arithmetic.

Just sayin' . . . . .

[and obviously, I personally need to just become more familiar with spec-profiles for the new DDR4 in a choice of speeds.]

 

[MongGrel]

Redacted, it's been said.

Tighter timings are faster better.

 

[BonzaiDuck]

Redacted, it's been said.

Tighter timings are faster better.

Except that speed trumps timing, in many but not all cases.

Why "redacted?" He asked the question, and I have too much time on my hands!

 

[ctk1981]

Voltage first, evaluate options, prefer lowest timing at highest speed...only with regards to cpu, dGpu. Apu, choose speed over latency, within reason.

 

[WildThane]

Thanks for the reply all, I get the basic Idea this will help me in a new build this fall.

 

[Dasa2]

This is only to be used as a rough guide and if there numbers are close the higher frequency kit is probably quicker

There is some real world numbers here the link also has read\write speed for comparison which while not of great importance in these tests can be to some software or as mentioned above to igp
CPU : DDR4 vs DDR3 en pratique - Intel Core i7-6700K, i5-6600K et Z170 : Skylake en test - HardWare.fr

With this showing a improvement in arma3 performance you need to keep in mind that the faster ram is only improving the efficiency of the cpu here as most games need random data that doesn't fit in there cache from the ram
Also most games are not like arma they are gpu bottlnecked so they dont see gains from improved cpu performance especially if the target fps is only 60 on a high res display

 

[BonzaiDuck]

I will feel more comfortable discussing the range of DDR4 options as I proceed to plan my i7-6700K system.

I don't build my systems to get the very best benchmarks, but to get good benchmarks. Price has a little to do with some of these issues, even if price of RAM seems cheap these days.

The system in which I take the greatest pride doesn't have the very best RAM. Its precursor -- they are more or less twin systems -- has a 2x8GB Ripjaws Z 1866 kit that runs at 9-9-9-24. My favorite -- the second system -- has Ripjaws X 9-10-9-28 1866. I bought them because they were about $30 cheaper, and I'm less inclined to spend money on these Gen-2 SB systems, despite the fact that I can't help myself. But you could still run the latter kit with CR=1, because G.SKILL makes good RAM kits.

I think I'd looked at a set of DDR4-2400 Ripjaws V, and perhaps some speedier entrants in that model line. You try and find the RAM with the best timings, and plan and plot what you'll do to go from there. And you try and find the RAM that runs at a speed the system will accommodate. For the motherboard I'm going to buy, that would probably be up to about 3000 Mhz.