Holly molly, that is some wicked s**t memory

G.Skill "is" or "are" you can't have have them both Hilbert 😀

since when is CL17 low? or even ultra low? maybe it is in terms of super high frequencies memory sticks?

My mobo isn't good enough.

tsunami231:

since when is CL17 low? or even ultra low? maybe it is in terms of super high frequencies memory sticks?

On 4266MHz cl!7 is very very low. Remember you can still buy 1600Mhz cl11 DDR3 memory so in that contest it is very low.We are her still talking about less then 0.5ns cycle time and less then 8ns for first word.

DStealth:

Curious to see some Aida64 results...As my memory is reducing speed after 3700-3800 while RTLs and IOLs are not tight also tRFC over 700(for these ultra-low latency mem..Wow 🙂 )...I have degradation after 350 by far even 200-300Mhz cannot even compansate in terms of transfer or latency... Here's my memory running 3770 14-14-14-28-280 2T with 4 dimms on Z370 and 4040 cl16-15-15-35-400 2T Just see write and copy... All the same...IMO it's just a marketing w/o real world performance benefits getting over 4Ghz[spoiler] http://cdn.overclock.net/8/8b/8be7791d_Aida64_sub35ns.jpeg http://cdn.overclock.net/7/75/7552ee5a_Aida64_4040c16.jpeg[/spoiler]

almost looks like you are maxingout the ringbus, have you tried setting the uncore even higher? (if thats even possible lol)

DStealth:

All the same...IMO it's just a marketing w/o real world performance benefits getting over 4Ghz

Well it depends. I agree is not a bottleneck having the memory at 3.8, 4 or more GHz. But someone has to push the pedal on the accelerator, someone does faster memories, and someone else will make faster memory controllers to take advantage of them.

thatguy91:

Timings are directly proportional to the RAM speed since they are measured in cycles.

HeavyHemi:

CL 17 latency at 4.2ghz is roughly equivalent to CL 8 latency at 2ghz. Plus the added bandwidth of the higher frequency RAM.

that make sense not sure why i didnt realize this., maybe my attempts to forget all things i know about computer tech is finally working:p

DStealth:

Not maxed can run synced with CPU ...but have to shave CPU OC to sub 5300 🙂) https://img01-olxbg.akamaized.net/img-olxbg/125064161_2_800x600_asrock-fatal1ty-z370-gaming-k6-snimki_rev002.jpg

You would expect the bandwidth to go up even with looser timings on 4000mhz, since you're still seeing bandwidth scaling with the higher uncore even with looser timings at 3845, it would seem that coffee lake can't make use of 4000+ speeds unless you are setting the uncore past 5.3ghz. Nice chip btw, truely amazing.

3200mhz is so 2014.. 4000 cl17 is pretty easy on CL, sky x and coffy L with b-die 3200cl14, 3600c15/c16 3733 c17 etc. Just add 1.4-1.45v 🙂

delete

MegaFalloutFan:

Can I ask you some questions about your overclock? What cooling do you use? CPU is Delided? Is it 27/7 setup or benchmark mode? Do you have Ring bus locked at the top speed or its down-clocking like CPU when idle? Im on Gigabyte Gaming 7, so far i just enabled CPU Upgrade 5Ghz from the mobo and it works, ill tweak manually later, see if i can push it passed 5Ghz Im on Corasir 110i, replaced their fans to two 140mm Noctuas I got Corsair 4266MHz 19.26.26.46.72 1.4v KIt, it was amazing at first, plugged it in, enabled XMP2 and everything worked, booted fine and no Zero issues.....until i decided to benchmark and got 16000 MB/s read and write LOL I tested RAM by choosing default (2333mhz) speed and got 31K, so i decided to test what will happen if i downlock it to 4000Mhz and to my amazement got 52404 MB/s READ, 57054 MB/s WRITE, 47384 MB/s COPY, 49.2 ns So far the only optimizing i did is lowering timing one digit down 19.25.25.45 and got 53185 MB/s READ, 57673 MB/s WRITE, 47384 MB/s COPY, 49.2 ns So, how did you achieved such low timing? did you increase the voltage or your RAM is just that good? you just lowered the timings and it holds?

That would be @DStealth 's setup, Should probably ask him lol.

DStealth:

Curious to see some Aida64 results...As my memory is reducing speed after 3700-3800 while RTLs and IOLs are not tight also tRFC over 700(for these ultra-low latency mem..Wow 🙂 )...I have degradation after 350 by far even 200-300Mhz cannot even compansate in terms of transfer or latency... Here's my memory running 3770 14-14-14-28-280 2T with 4 dimms on Z370 and 4040 cl16-15-15-35-400 2T Just see write and copy... All the same...IMO it's just a marketing w/o real world performance benefits getting over 4Ghz http://cdn.overclock.net/8/8b/8be7791d_Aida64_sub35ns.jpeg http://cdn.overclock.net/7/75/7552ee5a_Aida64_4040c16.jpeg

That drop happens when mobo auto raises 3rd timings to "compensate" for higher speeds. I saw the same by mine 2400 ok , 2666 drop by write and copy, when i tightened back 3rd timings similar to 2400 if flew over 40GB/s (was 31).. But for that I had to use more cpu sys agent voltage

-Tj-:

That drop happens when mobo auto raises 3rd timings to "compensate" for higher speeds. I saw the same by mine 2400 ok , 2666 drop by write and copy, when i tightened back 3rd timings similar to 2400 if flew over 40GB/s (was 31).. But for that I had to use more cpu sys agent voltage

Whats 3rd timings?

DStealth:

Curious to see some Aida64 results...As my memory is reducing speed after 3700-3800 while RTLs and IOLs are not tight also tRFC over 700(for these ultra-low latency mem..Wow 🙂 )...I have degradation after 350 by far even 200-300Mhz cannot even compansate in terms of transfer or latency... Here's my memory running 3770 14-14-14-28-280 2T with 4 dimms on Z370 and 4040 cl16-15-15-35-400 2T Just see write and copy... All the same...IMO it's just a marketing w/o real world performance benefits getting over 4Ghz

Can I ask you some questions about your overclock? What cooling do you use? CPU is Delided? Is it 27/7 setup or benchmark mode? Do you have Ring bus locked at the top speed or its down-clocking like CPU when idle? Im on Gigabyte Gaming 7, so far i just enabled CPU Upgrade 5Ghz from the mobo and it works, ill tweak manually later, see if i can push it passed 5Ghz Im on Corasir 110i, replaced their fans to two 140mm Noctuas I got Corsair 4266MHz 19.26.26.46.72 1.4v KIt, it was amazing at first, plugged it in, enabled XMP2 and everything worked, booted fine and no Zero issues.....until i decided to benchmark and got 16000 MB/s read and write LOL I tested RAM by choosing default (2333mhz) speed and got 31K, so i decided to test what will happen if i downlock it to 4000Mhz and to my amazement got 52404 MB/s READ, 57054 MB/s WRITE, 47384 MB/s COPY, 49.2 ns So far the only optimizing i did is lowering timing one digit down 19.25.25.45 and got 53185 MB/s READ, 57673 MB/s WRITE, 47384 MB/s COPY, 49.2 ns So, how did you achieved such low timing? did you increase the voltage or your RAM is just that good? you just lowered the timings and it holds?

MegaFalloutFan:

Whats 3rd timings?

Tertiary Timings: These are timings that are NEVER listed anywhere on a marketing page, and are different per motherboard/CPU IMC/ ram IC. They are generated by your IMC, after your board probes it repeatedly looking for a stable configuration. Some of you might have noticed your PC restarting a few times when installing new memory kits. These timings are often the cause of that, as they need special training in order for you to post properly. They include: tREFI tCKE tRDRD (_SG, _DG, _DD, _DR) tRDWR (_SG, _DG, _DD, _DR) tWRRD (_SG, _DG, _DD, _DR) tWRWR (_SG, _DG, _DD, _DR) Very specific boards and chipsets will allow modification of these timings. They are by far one of the most important groups of timings you can adjust, and are directly involved in improving your bandwidth efficiency. More on that later.

Especially trdrd and twrrd Read 4-6-6 Write 4-7-7 https://linustechtips.com/main/topic/773966-comprehensive-memory-overclocking-guide/