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Old 06-16-2019, 11:21 PM
A Computer Guy A Computer Guy is offline
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So it seems I found a nice middle ground with CMW32GX4M2C3200C16 where I have 32GB (2 sticks, dual rank) that runs at DDR4-3200 with a Ryzen 5 2600.

If I underclock it to DDR4-2933 the XMP timings entered manually work with no problem.

If I match the clock to DDR4-3200 this is where things got difficult as initially it wouldn't post 99% of the time.

I figured out when I was attempting to apply the settings from DRAM Calculator for Ryzen 1.5.1 to the BIOS/UEFI there was some additional technique involved that I had not been doing before when dealing with my Vengeance LPX sticks where I had significantly limited success.

Trying to input and apply all the settings all a once from DRAM Calculator into the ASRock BIOS/UEFI was not working and I found splitting up the saves allowed me to finally post at the higher frequency.
For example:
1) Set to DDR4-2133 with AUTO timings, save, reboot
2) Set procODT, RTT, and CAD_BUS options, save, reboot (this is what finally allowed me to post above DDR4-3200)
3) Set voltages for DRAM and SOC, save, reboot (for ASRock be sure to use the option "SOC OVERCLOCK VID" not that SOC offset option!)
4) Increase frequency, save, reboot
5) Set timings, save, reboot
6) Test and adjust

To prepare for entering timings I first prepared a worksheet from the SPD information with the memory timings in nanoseconds. I would use the nanosecond timings with the debug profile option in DRAM Calculator to calculate a safe JEDEC like profile for my target frequency.

Next this information is used to create another worksheet to calculate all timings that may work at the higher XMP frequency and their translation into nanoseconds. I would use these timings in nanoseconds with the debug profile option in DRAM Calculator to calculate a safe XMP profile for my target frequency.

With the worksheets and DRAM Calculator profiles I reconciled what timings to use and test with and additional settings.

To make a long story short here are the timings that worked for me.
Code:
DDR4-3200
 18 - tCL   (from XMP 16+2)
 18 - tRCD  (from XMP)
 18 - tRP   (from XMP)
 36 - tRAS  (from XMP)
 58 - tRC   (from XMP 54+4)
  6 - tRRDS (from XMP)
  9 - tRRDL (from XMP)
 36 - tFAW  (from XMP)
  4 - tWTRS
 12 - tWTRL
 12 - tWR
  6 - tRDRDSCL
  6 - tWRWRSCL
560 - tRFC  (calculated from SPD data) 
416 - tRFC2 (calculated from SPD data)
256 - tRFC4 (calculated from SPD data)
 18 - tCWL
 10 - tRTP
  6 - tRDWR
  3 - tWRRD
  1 - tWRWRSC
  7 - tWRWRSD
  7 - tWRWRDD
  1 - tRDRDSC
  5 - tRDRDSD
  5 - tRDRDDD
  8 - tCKE

DRAM = 1.35v
SOC = 1.012v (SOC OVERCLOCK VID = 54)
Gear Down Mode = Enabled
Power Down Mode = Disabled
BGS = Disabled
BGS-ALT = Enabled
ProcODT = 60 ohms
RTT_NOM = RZQ/7(34)
RTT_WR = RZQ/3(80)
RTT_PARK = RZQ/1(240)
CAD_BUS = All 24 ohms
The XMP values that refused to work were tCL at 16 and tRC at 54 and they needed adjustment to post.

I was able to calculate the tRFC values based on the SPD data. The BIOS/UEFI kept wanting to use 312 on AUTO but that simply would not work.

DRAM Calculator suggested 16 for tCL, tRCD, tRP, and 307-312 for tRFC however this just would not work.

According to SPD this kit is Samsung b-die however I suspect probably not the best quality b-die that does CL14 that you constantly hear about.

ASRock's ability to change the SOC voltage was a bit out of the way. You have to find an option called "SOC OVERCLOCK VID" and enter a hexadecimal value to change the voltage. I came across a German youtube video that provided the VID values. (probably due to BIOS/UEFI updates the VID values may be different) On my system the value "54"=1.016v, increase the value to lower the voltage, decrease the value to increase the voltage. There is a SOC offset option however don't use that. I found in using that the BIOS/UEFI pushed my SOC over 1.2v unexpectedly.

I hope this is helpful to those that want to use 32GB (2 sticks, dual rank) configuration at DDR4-3200 with Ryzen. (same settings work for DDR4-3266)

DDR4-2933 to DDR4-3200 makes a big difference. I couldn't get DDR4-3333 working without some awful timings, not worth it. (perhaps workable with better motherboard & cpu)

(edited post for more completeness)

Last edited by A Computer Guy; 07-01-2019 at 08:55 PM.
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