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Ryzen DRAM Calculator by 1usmus

What should I do next then? What about the other numbers!? Leave them on auto!? Latency improved a lot. 69 with your numbers.
69 ain't great, it's only slightly lower than stock defaults of 72. I would just run the 3600mhz setup above and call it a day. This is corsair right? I'd avoid that brand in the future.
 
69 ain't great, it's only slightly lower than stock defaults of 72. I would just run the 3600mhz setup above and call it a day. This is corsair right? I'd avoid that brand in the future.
Yes Corsair. Thanks for the help.

69 ain't great, it's only slightly lower than stock defaults of 72. I would just run the 3600mhz setup above and call it a day. This is corsair right? I'd avoid that brand in the future.
i just tried these without changing volts, everything else on auto.
 

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Yes Corsair. Thanks for the help.


i just tried these without changing volts, everything else on auto.
Ryzen 2 latency range is generally speaking 62ns-72ns with 72ns being default. Given your ram, any drop in latency you can get is a win but I wouldn't make it a huge concern because you won't notice the gains with the naked eye.
 
Yes Corsair. Thanks for the help.


i just tried these without changing volts, everything else on auto.

Unlike the original result, there's actually nothing wrong with these results at 3600. You can tighten up some of the timings if you understand how, but there's really not a lot that needs fixing. Now go verify your stability.

The XMP 4000 profile is essentially useless for you, because on Ryzen 3000 there's a 100% probability that it runs at decoupled Infinity Fabric speeds, basically meaning that your copy perf and latency are all getting slaughtered. IF limit of your chip probably runs 3600-3800, above that the IF penalty makes it pointless to run higher speeds. The 4000 XMP is at least a fallback in case nothing else works, but not much else.

Ryzen 2 latency range is generally speaking 62ns-72ns with 72ns being default. Given your ram, any drop in latency you can get is a win but I wouldn't make it a huge concern because you won't notice the gains with the naked eye.

68ns for 3600 16-18-18 on Ryzen 3000 is spot on, if not a little bit on the fast side considering tRFC is 350ns and all the timings are loose. When tightened up 16-19-19 is around the 69ns mark.
 
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@Antrax360
make sure to change at least ram voltage to fixed 1.35,
and as Tabascosauz said, verify its actually stable, use hci (dos mode is best) or TM5 (boot/running does not equal stable)


@thesmokingman
..I'd avoid that brand in the future...
lol. love those ppl recommending/disparaging ppl brands in general, when corsair doesnt even make the dies like many others.

i never had any issues with corsair ram in 20y (+50 personal builds), all running specs/expected, even with untested boards (as in QVL).
yet all those "forum recommendations" i got in the past 10y werent stable with xmp "specs", and in case of ryzen, three different gskill kits did not even post (4 different boards, 3 different brands),
while 2 of 3 corsair kits were coming with good dies (samsung/micron), performing without trouble (post without changing V thru different kit first),
and much better timings as well (cl15 vs 18).
 
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Yes Corsair. Thanks for the help.


i just tried these without changing volts, everything else on auto.
Thats nice results given the fact that you started from 76ns. With what DRAM voltage is this?

Memory bandwidth (GB/s) is also up. As other stated you dont want the MCLK/FCLK/UCLK to be decoupled as this is giving a significant latency penalty. Keep them all at 1800MHz.
There is always room for improvement, but from this point on the gains will be minimal.

If you feel like it you can try:
16-18-18-18-38 (first 5 of ZenTimings)
tRC: 56 (18+38)
tFAW: 28 (tRRDS x4)
tRFC: 456 (tRC x8+8)

All timings are related (add, subtract or multiply) to each other, and none of them are random numbers.

GDM (GearDownMode) Enabled as you have, its like having the Cmd2T to 1.5T instead of 1T. Though in order to disabled it you may have to increase DRAM voltage. It may not worth it for the improvement return.

----------------------------------------------------
As for Corsair RAM it all depends on the part number of sticks. Z series are the only "guaranteed" that will work with Ryzen and others may work or may not.
 
Thats nice results given the fact that you started from 76ns. With what DRAM voltage is this?

Memory bandwidth (GB/s) is also up. As other stated you dont want the MCLK/FCLK/UCLK to be decoupled as this is giving a significant latency penalty. Keep them all at 1800MHz.
There is always room for improvement, but from this point on the gains will be minimal.

If you feel like it you can try:
16-18-18-18-38 (first 5 of ZenTimings)
tRC: 56 (18+38)
tFAW: 28 (tRRDS x4)
tRFC: 456 (tRC x8+8)

All timings are related (add, subtract or multiply) to each other, and none of them are random numbers.

GDM (GearDownMode) Enabled as you have, its like having the Cmd2T to 1.5T instead of 1T. Though in order to disabled it you may have to increase DRAM voltage. It may not worth it for the improvement return.

----------------------------------------------------
As for Corsair RAM it all depends on the part number of sticks. Z series are the only "guaranteed" that will work with Ryzen and others may work or may not.
Theres three TrFc settings on my bios.
 

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Theres three TrFc settings on my bios.
You need to change only the first tRFC
tRFC2/4 can be on auto.

There is a relation between them but on a Ryzen system wont matter.

tRFC2 = tRFC / 1.346
tRFC4 = tRFC2 / 1.625
 
So 456 on first that's it!?

On every board with every kit I've owned it's been 192 and 132 for the other two, and I can confirm manually setting them makes no difference.

Some DRAM gurus confirmed early on that the current AMD BIOS pretty much either disregards or overrules what you enter as tRFC2 and tRFC4
 
On every board with every kit I've owned it's been 192 and 132 for the other two, and I can confirm manually setting them makes no difference.

Some DRAM gurus confirmed early on that the current AMD BIOS pretty much either disregards or overrules what you enter as tRFC2 and tRFC4
It doesn't boot when I tried manually adjusting those values. So left them on auto. At least the first tRFC.
 
It doesn't boot when I tried manually adjusting those values. So left them on auto. At least the first tRFC.

If you have Micron Rev.E, tRFC is not your strong suit, use the chart as a starting point:

The chart starts getting sketchy at the extremely fast end with B-die, but you're at the slow end. Go too low on tRFC for your IC at a certain speed, and you will not boot.

Reous tRFC list v21 (1).png
 
@Antrax360
So according to the chart above you can’t go lower than around 550 so choose 560 if your tRC is 56 (560 = tRC x10)
 
Got a Patriot Viper 2x8 4400cl19 B-die kit a while back and started tweaking it a few days ago. However I have some trouble. The fast 3733cl16-profile is supposed to work with GDM off, but even with GDM on I only get it stable at 1.42V. Without gdm it's unstable at 1.45V aswell. 3733cl14@1.49V seems stable, but that voltage is a bit over my preference. On my previous ram, micron rev E I had no problems running 3733cl16 gdm off at 1.38V and 3733cl15@1.43V, even lowered several subs further on both these settings. I know B-die is a bit more taxing on IMC due to tighter tRCD, tRC and tRFC, but didn't think difference would be that big. Any tips for getting it stable at lower voltage? 2T better choice? Any app I can monitor ram temp? Found no info on temp in hwmonitor64. Maybe cl15 with 2T?
 
Got a Patriot Viper 2x8 4400cl19 B-die kit a while back and started tweaking it a few days ago. However I have some trouble. The fast 3733cl16-profile is supposed to work with GDM off, but even with GDM on I only get it stable at 1.42V. Without gdm it's unstable at 1.45V aswell. 3733cl14@1.49V seems stable, but that voltage is a bit over my preference. On my previous ram, micron rev E I had no problems running 3733cl16 gdm off at 1.38V and 3733cl15@1.43V, even lowered several subs further on both these settings. I know B-die is a bit more taxing on IMC due to tighter tRCD, tRC and tRFC, but didn't think difference would be that big. Any tips for getting it stable at lower voltage? 2T better choice? Any app I can monitor ram temp? Found no info on temp in hwmonitor64. Maybe cl15 with 2T?

Disregard DRAM Calc. When you start getting into higher speeds on good B-die, 1usmus' recommendations start making less and less sense. Keep GDM on if you want to daily high speed B-die without pushing 1.6V.

The Viper Steels do not have temp sensors. You will not find any temps displayed on any software. Keep em cool with airflow, but unless your computer is baking over a heater or fireplace, they are SR sticks and don't get overly hot.

CL14 isn't easy for even good B-die. You just compensate with VDIMM within reason, strike a good balance for tRFC (which is very VDIMM bound), or drop tRCD and tRP to 16 for less great B-die. No reason to be afraid of 1.5V, as long as you can keep it cool under GPU heat.

B-die you will generally run at flat timings (or close to flat) across tCL-tRCD-tRP. Once you've gotten to that baseline, tRFC is basically singlehandedly carrying your performance further, but is often an exercise in juggling VDIMM and airflow. Use the Reous tRFC chart to start, find the lower limits of your sticks, then start finding out what is stable at the VDIMM you want to run. Loose tRFC makes it completely pointless to run fast B-die.

Go off the Memtesthelper guide if you need a good place to start developing your own experience. A good place to start for high speed B-die, DRAM Calculator really is not.
 
Got a Patriot Viper 2x8 4400cl19 B-die kit a while back and started tweaking it a few days ago. However I have some trouble. The fast 3733cl16-profile is supposed to work with GDM off, but even with GDM on I only get it stable at 1.42V. Without gdm it's unstable at 1.45V aswell. 3733cl14@1.49V seems stable, but that voltage is a bit over my preference. On my previous ram, micron rev E I had no problems running 3733cl16 gdm off at 1.38V and 3733cl15@1.43V, even lowered several subs further on both these settings. I know B-die is a bit more taxing on IMC due to tighter tRCD, tRC and tRFC, but didn't think difference would be that big. Any tips for getting it stable at lower voltage? 2T better choice? Any app I can monitor ram temp? Found no info on temp in hwmonitor64. Maybe cl15 with 2T?
Why are you so worried about voltage? DDR4 pulls very little power. 1.5v is perfectly fine for daily usage. And B-die scales very well with voltage. I have the same kit (two actually) running in 4x8 configuration and i just copied Buildzoid's settings for these from one of his videos:
BUILDZOID 3800 C14:
Primary:
tCL: 14
tRCDRD: 16
tRCDWR: 13 (might do 8)
tRP: 13
tRAS: 27 (might do 21)

Secondary:
tRC: 40
tWR: 12 (might do 10)
tCWL: 12
tRRD_S: 4
tRRD_L: 4
tWTR_S: 4
tWTR_L: 8
tRFC: 300 (might do 260-280)
tRFC2: 300
tRFC4: 300
tRTP: 10
tFAW: 16

Tertiary:
tRCPAGE: Auto
tRDWR: 11
tRDRDSC: 1
tRDRDSD: 4
tRDRDDD: 4
tRDRD_SCL: 3
tWRRD: 1
tWRWRSC: 1
tWRWRSD: 6
tWRWRDD: 6
tWRWR_SCL: 3
tCKE: 1

Termination:
ProcODT: 36,9 ohm
tCMD: 1T
GDM: Enabled

ClkDrvStren: 24 ohm
AddrCmdDrvStren: 20 ohm
CsOdtDrvStren: 24 ohm
CkeDrvStren: 24 ohm

RttNom: RZQ/7
RttWr: RZQ/3
RttPark: RZQ/1
 
Thx for fast reply :) dram calc worked perfect for rev E, too bad it doesn't for B-die :/ What would you say is upper voltage limit for 24/7? I mine when I don't game or do productivity. Gpu has a vent which blow air over ramstick and cpu-cooler and exhaustvent draw it away, they don't seem to get very hot so far, but I have a random reboot once or twice a day when I ran my ram at 1.48V which seemed stable in shorter memtest, but was apparently not. 3733cl14 has superb performance (105sec on dram calc test vs 112 on best rev E setting, aida latency is 64 vs 66), but don't wanna risk lifespan.

Why are you so worried about voltage? DDR4 pulls very little power. 1.5v is perfectly fine for daily usage. And B-die scales very well with voltage. I have the same kit (two actually) running in 4x8 configuration and i just copied Buildzoid's settings for these from one of his videos:
Thx for reply. What voltage did he run it at? Maybe I worry too much about it, I thought 1.5V was birderline safe. Anything I should change with that preset when running 2x8 instead of 4x8?
 
He was running 1.5v:

30:32 onwards in video.
 
Overclocked?
Methinks the title is totally wrong and should mention timings were tuned. :kookoo:
Overclocking is not just upping the frequency like the name would suggest. Overclocking is everything that runs on manual settings and results in higher performance.
 
Overclocking is not just upping the frequency like the name would suggest. Overclocking is everything that runs on manual settings and results in higher performance.
That's called "tuning"
 
He was running 1.5v:

30:32 onwards in video.
I found this one after browsing his channel:
with oc/tuning with 2 sticks, might be even closer to what I can expect :)
 
Got a Patriot Viper 2x8 4400cl19 B-die kit a while back and started tweaking it a few days ago. However I have some trouble. The fast 3733cl16-profile is supposed to work with GDM off, but even with GDM on I only get it stable at 1.42V. Without gdm it's unstable at 1.45V aswell. 3733cl14@1.49V seems stable, but that voltage is a bit over my preference. On my previous ram, micron rev E I had no problems running 3733cl16 gdm off at 1.38V and 3733cl15@1.43V, even lowered several subs further on both these settings. I know B-die is a bit more taxing on IMC due to tighter tRCD, tRC and tRFC, but didn't think difference would be that big. Any tips for getting it stable at lower voltage? 2T better choice? Any app I can monitor ram temp? Found no info on temp in hwmonitor64. Maybe cl15 with 2T?
I will agree with previous suggestions. As for voltage and what would be ok for 24/7 depends on Ram module temp. As said, b-dies scale nicely with voltage as long as you keep it cool. If you can keep it cool, even 1.6V is ok for 24/7. If cooling is inadequate errors will appear rather quickly. If your sticks have temp sensors then it would appear on ThaiphoonBurner.
 
@Taraquin
what memtest are you using?
some will show errors only if sticks are defective (more or less), but not any problems with clocks/timings/voltage..
testing under win is usually not good (you cant test all ram), so i recommend hci (buy the 15$ deluxe, allows boot from stick),
and test to 100% to verify settings, to 400% to see if your stable, better to 1000%..
 
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