DRAM calculator for Zen 3

[Anonymous1243]

@Dreamic - You said latest BIOS.. is that 7C91vA51(Beta version) or 7C91vA4 ? I believe I read the one that activates SAM (7C91vA51) is known to have issues with hitting high FCLK.

EDIT: If you're on the beta, try flashing 7C91vA4 and try again.

7C91vA51, I actually got my 2nd 2x8gb kit for dual rank delivered the same day which I was waiting for and the WHEA/performance issues to be fixed before trying 3200/1600+. I could go back try to post 1900 but I heard others still are, and regardless going to need a new BIOS with fix if that's the case, which hopefully it is that would be nice.

 

[thesmokingman]

@Taraquin @Ampeg
Yea I just can't boot at 1900 FCLK, and I haven't tried 3800mhz because there's no point getting it stable if I can't boot 1900.
Currently testing 1867 but I don't think I can get CL14 3733

AIDA 55ns latency, BIOS cannot set tRRDS lower than 4

If you cannot boot with those settings that's your sign that that setting doesn't fit your ram. It's like pushing a square peg down a round hole. Look at the dram pcb revision drop down, A0 is like regular bin and A3 is like newer faster bin. Regardless ya have to find timings that work first. If nothing works then set timings to real slow then work ya way down. Stop shoving that square peg...

 

[Anonymous1243]

If you cannot boot with those settings that's your sign that that setting doesn't fit your ram. It's like pushing a square peg down a round hole. Look at the dram pcb revision drop down, A0 is like regular bin and A3 is like newer faster bin. Regardless ya have to find timings that work first. If nothing works then set timings to real slow then work ya way down. Stop shoving that square peg...

Shouldn't it not matter if I can't even post 1900 FCLK with RAM at default 2133mhz? It's Patriot 4400C19 B-Die. I imported XMP into DRAM Calc from Thaiphoon. It's 100% stable at 3600C14 TM5 1usmus overnight and 3733C16 settings I posted so far for a couple hours, about to run overnight. I'm certain it can run 3800 and it's not the RAM holding me back, I can test 3800 tomorrow but there's not much of a point cause I lose 1:1 if CPU/Mobo BIOS can't hit 1900. I might check old BIOS as Ampeg suggested but that has issues of its own above 3200

 

[Taraquin]

@Taraquin @Ampeg
Yea I just can't boot at 1900 FCLK, and I haven't tried 3800mhz because there's no point getting it stable if I can't boot 1900.
Currently testing 1867 but I don't think I can get CL14 3733
View attachment 176101
AIDA 55ns latency, BIOS cannot set tRRDS lower than 4

If you want 1900 IF you must probably set SOC to 1.125V and VDDG IOD to 1.075V. SOC must always be 50mv higher than VDDG. Maybe a bit higher, my highest comfortable value is 1.15V soc and 1.1 vddg, but I know other who use up to 1.2V soc and 1.15V vddg daily. TRRDS is in a 1:4 ratio with tFAW. Lowest active values are 4 and 16. Below that is not active values. You can try lowering tWR and tRRDL to 6, if that work try 4. TWR can be lowered to 12 and maybe 10. TRP will probably go lower, 11-13 should be possible. TRC might go a bit lower aswell.

 

[Anonymous1243]

If you want 1900 IF you must probably set SOC to 1.125V and VDDG IOD to 1.075V. SOC must always be 50mv higher than VDDG. Maybe a bit higher, my highest comfortable value is 1.15V soc and 1.1 vddg, but I know other who use up to 1.2V soc and 1.15V vddg daily. TRRDS is in a 1:4 ratio with tFAW. Lowest active values are 4 and 16. Below that is not active values. You can try lowering tWR and tRRDL to 6, if that work try 4. TWR can be lowered to 12 and maybe 10. TRP will probably go lower, 11-13 should be possible. TRC might go a bit lower aswell.

Thanks, it just doesn't want to boot even with 1.2 and 1.15. Might try old BIOS if I'm really bored to see but it has its own issues not something I'd want to stay on so would be kinda a waste of time. I guess I just have to hope for a new BIOS to work and revisit then. These are my results for now, I might try lowering subtimings as you said but is there anything I can do to get tCL to 14? DRAM Voltage is already 1.5 and with all other stable settings the same only changing tCL 16 to 14 it gives out an error within a minute.

 

[thesmokingman]

Shouldn't it not matter if I can't even post 1900 FCLK with RAM at default 2133mhz? It's Patriot 4400C19 B-Die. I imported XMP into DRAM Calc from Thaiphoon. It's 100% stable at 3600C14 TM5 1usmus overnight and 3733C16 settings I posted so far for a couple hours, about to run overnight. I'm certain it can run 3800 and it's not the RAM holding me back, I can test 3800 tomorrow but there's not much of a point cause I lose 1:1 if CPU/Mobo BIOS can't hit 1900. I might check old BIOS as Ampeg suggested but that has issues of its own above 3200

Dude, it depends on your settings. Hitting 1900 and 2000 isn't always easy. Btw, I've run that ram before at 3800mhz at cas 15 or 14 iirc and I didn't need voltage on soc. Hell imo, ppl create more problems than help by adding too much soc voltage.

When I am testing, I only set the primary timings and real slow at that, then I leave everything else on auto. The secondary and tertiary timings can sink your efforts just like the primary timings so keep that in mind. Don't touch GDM and PDM until you get something stable and even then GDM is often hard to disable.

 

[Taraquin]

CL is not that important, and you must set voltage higher to stabilize it, 1.5V is borderline high already. Try CL15 first, if thats unstable keep CL16. Try lowering tWR to 12 or 10 and tRRDL to 6 or 4, also tRFC might go to 250-280 range.

 

[Anonymous1243]

Dude, it depends on your settings. Hitting 1900 and 2000 isn't always easy. Btw, I've run that ram before at 3800mhz at cas 15 or 14 iirc and I didn't need voltage on soc. Hell imo, ppl create more problems than help by adding too much soc voltage.

When I am testing, I only set the primary timings and real slow at that, then I leave everything else on auto. The secondary and tertiary timings can sink your efforts just like the primary timings so keep that in mind. Don't touch GDM and PDM until you get something stable and even then GDM is often hard to disable.

Ok I reset BIOS to defaults, entered only 3200mhz, 19 19 19 39 68, 1.5v DRAM, everything else on Auto/Default, only boots up to 1867 FCLK. I can basically do whatever I want and it will boot 1867 no problem. I'll try cas 14 again with subtimings Auto at some point, I already have with GDM and voltages Auto besides DRAM 1.5v

CL is not that important, and you must set voltage higher to stabilize it, 1.5V is borderline high already. Try CL15 first, if thats unstable keep CL16. Try lowering tWR to 12 or 10 and tRRDL to 6 or 4, also tRFC might go to 250-280 range.

Yea I'm not going higher than 1.5v hopefully I can lower it a bit, when I try CL15 it just goes to CL14. I might just live with how the subtimings are until new BIOS comes out, maybe I can hit 1900 then and lower them.

 

[Taraquin]

Ok I reset BIOS to defaults, entered only 3200mhz, 19 19 19 39 68, 1.5v DRAM, everything else on Auto/Default, only boots up to 1867 FCLK. I can basically do whatever I want and it will boot 1867 no problem. I'll try cas 14 again with subtimings Auto at some point, I already have with GDM and voltages Auto besides DRAM 1.5v


Yea I'm not going higher than 1.5v hopefully I can lower it a bit, when I try CL15 it just goes to CL14. I might just live with how the subtimings are until new BIOS comes out, maybe I can hit 1900 then and lower them.

Since you have dual rank that makes it harder to lower CL and run higher speed. As I said, please tune the values I suggested, they will improbe oerformance. You must lower tCWL to 15 or 14 to get CL to 15 or 14 since they are connected. 14 I think is impossible for you, it requires a lot more voltage to ram, I need 0.07V more to get 14 stable, but 15 might go. Can you try cl15, tcwl 15/14, twr 12/10, tRFC 280 or lower and report back?
I can run 3733cl16 at 1.38V, 3733cl15 at 1.42V, but need 1.49V for 3733cl14, and I need to increade tRCDRD and twtrs a bit with higher voltage which negatively affects performance. I have Micron rev E and single rank so not directly comparable to you.

 

[Anonymous1243]

Since you have dual rank that makes it harder to lower CL and run higher speed. As I said, please tune the values I suggested, they will improbe oerformance. You must lower tCWL to 15 or 14 to get CL to 15 or 14 since they are connected. 14 I think is impossible for you, it requires a lot more voltage to ram, I need 0.07V more to get 14 stable, but 15 might go. Can you try cl15, tcwl 15/14, twr 12/10, tRFC 280 or lower and report back?
I can run 3733cl16 at 1.38V, 3733cl15 at 1.42V, but need 1.49V for 3733cl14, and I need to increade tRCDRD and twtrs a bit with higher voltage which negatively affects performance. I have Micron rev E and single rank so not directly comparable to you.

I tried but to enable CL15 I have to disable GDM right which makes it not even close to stable, and I can't set tcwl 15, BIOS goes 16 or 14. So I guess I'm at CL16 which might run at 3800 or higher but doesn't really matter as long as FCLK is stuck 1867. I did lower the subtimings a bit and run overnight but didn't really make a difference to read or latency, still 55ns.

As far as this list goes it's not terrible but my read speed does seem kinda low and it would've been nice to get into the 53ns 54ns range https://docs.google.com/spreadsheet...0MWVPcYjf6nOlr9CtkkfN78tSo/edit#gid=321590489
The only person at 3733 or less beating me has 1.7v... If I can ever get 1900 FCLK and 3800 that will bump me up a bit

 

[SirMaster]

Hi guys

I am new to Ryzen and pretty new to DRAM overclocking.

I figured I would post what I have achieved so far and see if any of you more knowledgeable people have any suggestions as for what I should do for further performance tweaking.

So far this seems stable as I have run HCI memtest (many instances to 90% utilization) for over an hour.

I have my DRAM voltage set at 1.48 which seems to result in 1.5 as reported in Windows monitoring tools such as HWiNFO64.

Thanks!

 

[Space Lynx]

nice latency! best I can do is 57.2ns, but I am on 32gb 2x16 kit

@SirMaster if you are stable there, leave it and enjoy! once new BIOS comes out, ram OC'ing should be better then. should be a a few months away. not sure. it will also enable 4000 1:1 more broadly.

 

[SirMaster]

Thanks!

I tried 4000 1:1, and it boots and even can run AIDA64 and some short benchmarks, but it's not generally stable, though I did not tune voltages much so perhaps it's possible.

Though when I did have it running I had the timings looser like CL16, and the AIDA64 latency was like 62ns which is much worse. Though the bandwidth was slightly higher, over 60,000MB/s. Maybe the latency was higher for some other reason like not full stability.

I can revisit 4000 IF later when there are new BIOS.

Yeah I am certainly happy with my current numbers, though I paid a pretty penny for this DRAM (https://www.newegg.com/g-skill-16gb-288-pin-ddr4-sdram/p/N82E16820232968)

I am quite happy that I have 2 separate sets of it running together like this for the dual rank interleaving benefit.

Just wasn't sure if I should try to explore lowering any of the latencies any further.

I am a little wondering about the Termination Block settings. The calculator recommends RZQ/7, OFF, RZQ/5, but I am currently running at RZQ/7, RZQ/3, RZQ/3. This is because at first I couldn't find these settings. Later I did find them and tried the recommended ones but it seemed to be less stable, so I put them back to the default values.

What do these 3 settings mean and how does adjusting them normally affect stability?

 

[Taraquin]

I tried but to enable CL15 I have to disable GDM right which makes it not even close to stable, and I can't set tcwl 15, BIOS goes 16 or 14. So I guess I'm at CL16 which might run at 3800 or higher but doesn't really matter as long as FCLK is stuck 1867. I did lower the subtimings a bit and run overnight but didn't really make a difference to read or latency, still 55ns.
View attachment 176256
As far as this list goes it's not terrible but my read speed does seem kinda low and it would've been nice to get into the 53ns 54ns range https://docs.google.com/spreadsheet...0MWVPcYjf6nOlr9CtkkfN78tSo/edit#gid=321590489
The only person at 3733 or less beating me has 1.7v... If I can ever get 1900 FCLK and 3800 that will bump me up a bit

You can probably lower tRP (I use 11 at 3733) a bit more, tRRDL can sometimes be run at 4, tWR might do 10, tRC might do 45, 46 or 47. Try that. It seems like you are maxed out elsewhere.

Hi guys

I am new to Ryzen and pretty new to DRAM overclocking.

I figured I would post what I have achieved so far and see if any of you more knowledgeable people have any suggestions as for what I should do for further performance tweaking.

So far this seems stable as I have run HCI memtest (many instances to 90% utilization) for over an hour.

I have my DRAM voltage set at 1.48 which seems to result in 1.5 as reported in Windows monitoring tools such as HWiNFO64.

Thanks!

View attachment 176321

View attachment 176318

View attachment 176319

Mostly good The most obvious is tWR. 10 or 12 should work, tRTP 10 or 8, tRP 11-14 (lowest stable), tRC 45-47, tRFC should get below 300. I have seen others with DR do 260 at 3800

 

[SirMaster]

Mostly good The most obvious is tWR. 10 or 12 should work, tRTP 10 or 8, tRP 11-14 (lowest stable), tRC 45-47, tRFC should get below 300. I have seen others with DR do 260 at 3800

Thanks!

New results so far:

 

[Taraquin]

Thanks!

New results so far:

View attachment 176432

View attachment 176433

Good. I think tRRDL can do 6 or 4, tWR 12 and perhaps a bit below 300 on tRFC, but you are probably close to the limit now

 

[SirMaster]

Good. I think tRRDL can do 6 or 4, tWR 12 and perhaps a bit below 300 on tRFC, but you are probably close to the limit now

Yeah I am not 100% pushing everything to the absolute max quite yet but I will proplay play with it more at some point.

Thanks again!

 

[Anonymous1243]

Needed a fan blowing on the RAM, 1.53v

 

[Dux]

What is more important for ZEN performance, RAM frequency or latency? If i had to choose between lower clocked RAM with tighter latency or higher clocked with looser latency.

 

[SirMaster]

What is more important for ZEN performance, RAM frequency or latency? If i had to choose between lower clocked RAM with tighter latency or higher clocked with looser latency.

I’m pretty sure it depends on what you are doing, the specific workload.

 

[thesmokingman]

What is more important for ZEN performance, RAM frequency or latency? If i had to choose between lower clocked RAM with tighter latency or higher clocked with looser latency.

Latency is best. Lower latency with high speed is even better, but if you cannot have both low latency is king.

 

[Alyjen]

So if I wanted to go from here (it's stable at 1.35V) to CL 14 (as I don't see any option to disable GDM how high voltage I'd have to apply?
What other settings (ProcODT?, CAD_BUS?) I'd have to adjust? Don't mind VSOC & rest of voltages, I had to adjust them anyway s ASUS on auto is putting some random values there.

I'm thinking about 24x7 stable, gaming/working rig, I'm not interested in benchmark pushing just for the sake of it. Or shall I wait for new BIOS and hope that FCLK 2000 will be stable? Currently I can boot with FLCK 2000 but it throws ton of WHEA warnings and performance is lower than 1900

 

[Taraquin]

So if I wanted to go from here (it's stable at 1.35V) to CL 14 (as I don't see any option to disable GDM how high voltage I'd have to apply?
What other settings (ProcODT?, CAD_BUS?) I'd have to adjust? Don't mind VSOC & rest of voltages, I had to adjust them anyway s ASUS on auto is putting some random values there.

I'm thinking about 24x7 stable, gaming/working rig, I'm not interested in benchmark pushing just for the sake of it. Or shall I wait for new BIOS and hope that FCLK 2000 will be stable? Currently I can boot with FLCK 2000 but it throws ton of WHEA warnings and performance is lower than 1900


View attachment 176676

For CL14 I bet you must raise dram voltage to atleast 1.45V. You can probably lower tRP, tRC and tRFC a bit more at your current voltage, except for that your timings look very good. I guess 14-14-14-28-45 250-280 tRFC is doable at 1.45V.

 

[Alyjen]

For CL14 I bet you must raise dram voltage to atleast 1.45V. You can probably lower tRP, tRC and tRFC a bit more at your current voltage, except for that your timings look very good. I guess 14-14-14-28-45 250-280 tRFC is doable at 1.45V.

Thanks, I may give it a try, memory is rated to run at 1.45V with it's top XMP so I'd consider it safe.
Playing with timings seems way easier than trying to disable geardown mode last time I went for that to set CL15 (which is pretty easy for this memory kit) I ended up with fresh Win 10 install

 

[Taraquin]

With GDM off I have to raise voltage by 0.03V, for each number I lower CL I must raise voltage by 0.05-0.07V. 3733cl16 with tweaked subs is stable at 1.35V, GDM req 1.38V, 3733cl15 req 1.43V and 3733cl14 req 1.49V. I have Micron rev E so not directly comparable.