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X570 Crosshair VIII Hero: Relationship Between BIOS and Ryzen DRAM Calculator

Level 10
I've never overclocked before and thought I'd start by overclocking the memory. I need some help mapping what the Ryzen DRAM Calculator (v 1.62):

says I should use to the fields in my X570 Crosshair VIII Hero's BIOS.

Currently, everything related to overclocking in the BIOS is the default "Auto" except that I've set it to use the D.O.C.P. profile in the memory.

Into the DRAM Calculator, I've entered what I believe to be the correct values for my system:
  • Processor: "Ryzen 2 gen" (which should be my Zen2 3700X)
  • Memory Type: Samsung B-die (I'm pretty sure - RAMMon says Samsung, the web says b-die)
  • Profile version: V1 (that's what people say to use)
  • Memory Rank: 1 (ditto)
  • Frequency (MT/s): 3200 (that's what the memory is rated for, so I used it as the safest)
  • BCLK: 100 (unchanged in BIOS)
  • DIMM Modules: 2
  • Motherboard: X570

(My memory consists of two banks of G.Skill F4-3200C14D-16GTZ DDR4, so that's where much of the above comes from)

I hit the purple "R-XMP" button at the bottom and it grabbed the timing information from my memory to complete the left column. I then hit the green "Calculate SAFE" button to get safe overclocking values.


I've managed to map the center values on the Calculator's "Main" page (the t... timings) to values in my BIOS. But, I'm at a loss for about half of the values in the right column. Could someone point me in the right direction for finding the place to set the following Recommended values in my BIOS?
  • DRAM Voltage: 1.35
  • SOC VOltage: 1.025
  • cLDO VDDG Voltage : 0.900
  • cLDO VDDP Voltage: 0.900
  • BGS: Disabled

Then, there's the Calculator's "Advanced" page where I can't find anything equivalent in my BIOS. Ditto for its "Power Supply System" page. I'd appreciate any help there, too. I've included screenshot of those pages since there's too much to type here.

83025 83026

ationfictons wrote:
I've found what I think are the locations for two other Calculator fields in the BIOS. I'd appreciate it if someone could confirm/deny those:

  • Under the Misc table, "BGS" (and the Alternate) might be "BankGroupSwap" at Advanced > AMD CBS > UMC Common Options > DRAM Memory Mapping
  • Under the Main Voltage table, "VRef (CHA/CHB)" might be "DRAM Ctrl Ref Voltage on" (CHA/CHB) at Extreme Tweaker > Tweaker’s Paradise

You have some good work here, I thought similar when I got to the BIOS and not all the settings were in one area, some are buried as you have found or dont relate with the exact terminology.

My board is the TUF B450-Gaming so it has close menu. I will revisit one day but was waiting for the BIOS' to settle which they seem to be churning out now.

Level 9
I recommend poking around in the Advanced Tab in Bios scroll down to the bottom "AMD Overclocking" where you will be greeted with a prompt to accept. You'll be greeted with 8 subtopics. VDDP & VDDG Voltage Control among them and I suspect all you are missing can be found there.


There is another alternative to adjusting VDDP & VDDG which is using Ryzen Master. The only problem I have with it is we have no idea what all the changes it makes other than what we manually adjust through the app. I know this much, I can run my system at 4450 all cores which are 3hrs Real Bench Stress Test stable by making two changes in the app but the same two change made to the bios fails to boot. To me that is a clear indication there is way more going on there than we see.


This may also answer the question of which SOC voltage to change. It makes sense to me to change the VDDCR SOC voltage other than system-wide SOC.

To be clear, I'm still on 1105 bios and unless I find a compelling reason to update to 1201 I will stick with it.
In any case, this is my effort to avoid confusion.

I understand release notes indicate " Update auto-rules for CPU and Memory overclocking" but we are not using auto are we?
Of course, there is always the unknown that may prove valuable so I never say never.
I've been overclocking for 20+ years and as a rule of thumb, I never update bios unless I need to. Back when you could replace the EPROM chip too. I even had Tski program a chip and send it to me once for an NF4 board.

I want to thank you @ationfictons for all the effort you have put forth here and offer you whatever input I can to help see it all to a successful end.

I too am looking to dot all my i's and cross all my t's before committing the tuned timings to bios and testing.

Suffice to say, I have a vested interest.

I'm working with Trident Z NEO memory specifically F4-3600C16Q-32GTZN
Using Thaiphoon my memory shows up as DJR which is not an available option in the drop-down menu. Imagine my concern so, I reached out to 1usmus through twitter and he responded within 2 days. I have no personal relationship with him/her and was quite grateful for the reply. Turns out we can use the "Hynix CJR" option when DJR parts are detected. Although I remain a bit skeptical I feel a bit better proceeding.


At this point I will continue working on the unanswered question so maybe we can cleanup post 2

I think I found CAD_BUS settings
Advanced>AMD CBS

I found VPP Voltage setting but in an unconventional way.
From In Bios tap "F9" type in "VPP" in the resulting dialog enter the value desired.

I think VDDCR may be adjusted by a CPU offset voltage vs an actual enty in bios. ATM I don't have a tool to monitor changes so I cannot be sure.
| Ryzen 9 3900X | ASUS ROG C8H | Trident Z Neo 4x8 3600 C16 | EVGA RTX2080Ti Ultra | EVGA Supernova 1000 G2 | Corsair 1TB MP600 (OS) & Samsung 970 evo 1TB M.2 (Games) | Custom Enthoo Luxe | EK-Quantum (CPU & Mobo) | Hydro Copper (2080Ti) | Custom external loop w/Phoyba Xtreme Nova 1080 |

In the end, I decided to go (roughly) with various bits of advice I got from here and other places and only overclock my memory up through the Calculator's CAD_BUS Block Resistances using the FAST settings for its rated 3200 speed. For my particular G.Skill F4-3200C14D-16GTZ DDR4 memory those numbers, and their locations, work out to be:

T-variables3200 FAST t-valuesBIOS Location: All under Extreme Tweaker > DRAM Timing Control
tCL14DRAM CAS# Latency
tRCDWR14Switch order
tRCDRD14Switch order
tRFC (alt)256Can’t find - ignored

Voltage Block (voltage range)3200 FAST RecBIOS Location: All under Extreme Tweaker
DRAM Voltage1.365
SOC Voltage1.025"CPU SOC Voltage"?
cLDO VDDG Voltage0.9Can't Find - ignored
cLDO VDDP Voltage0.9Wrong Units? 700 vs 0.9? Ignored

Misc Items3200 FAST ValueBIOS Location
Power Down modeDisabledExtreme Tweaker > DRAM Timing Control
Gear Down modeDisabledExtreme Tweaker > DRAM Timing Control
Command Rate1TExtreme Tweaker > DRAM Timing Control
BGSDisabledBankGroupSwap at Advanced > AMD CBS > UMC Common Options > DRAM Memory Mapping
BGS altEnabledBankGroupSwap Alt at Advanced > AMD CBS > UMC Common Options > DRAM Memory Mapping
FCLK1600Extreme Tweaker

Termination Block Resistances3200 SAFE/FAST RecBIOS Location: All under Extreme Tweaker > DRAM Timing Control

CAD_BUS Block Resistances3200 SAFE/FAST RecBIOS Location: All under Extreme Tweaker > DRAM Timing Control
CAD_BUS ClkDrv24"MemCadBusClkDrvStren"?
CAD_BUS AddrCmdDrv20"MemCadBusAddrCmdDrvStren"?
CAD_BUS CsOdtDrv20"MemCadBusCsOdtDrvStren"?
CAD_BUS CkeDrv24"MemCadBusCkeDrvStren"?

Basically, the only items I skipped were the cLDO VDDG Voltage and cLDO VDDP Voltage settings. Everything breezed through my stress testing and benchmarks without problem. I just updated to the 1201 BIOS and in the process reset all my BIOS settings. I considered just doing the memory overclocking in Ryzen Master but decided to stay with doing it in the BIOS (and that's fairly easy, now, since I know where the settings are). Since I do see those cLDO setting right there under RM's "Voltage Controls" area, I've been considering setting up a profile just to include those changes. But, since I'm running fine, I decided to be lazy and leave things alone. Also, I've seen posts mentioning that making changes in RM means it sets the values in the AMD Overclocking area and that area doesn't get cleared with setting the BIOS back to defaults. If something gets badly messed up doing things that way, I'd have to re-flash the BIOS to recover:

BTW: my benchmarks are mostly by eyeball, but according to the tests I ran, I'm getting about half a percent to a full percent more performance just from updating the BIOS from 1105 to 1201. It's really not worth mentioning (it's small enough to be considered noise), but it seemed consistent.

The results are from testing the Ryzen Dram Calculator Fast Settings on Samsung b-die certified 4133 at various speeds.
Ryzen 3900x with Ram 2x8 PVR416G413C9K

3600 Full Profile Fast Settings -

3666 Full Profile Fast Settings -

3733 Full Profile Fast Settings -

3800 Full Profile Fast Settings -


I have attached the full profile bios settings for each speed and made adjustments to some from the calculators suggestions. I run my system DDR4@3600 Fast Profile (daily driver) and I did stability test every profile prior to posting (they all work in my system, yours maybe different story bla bla bla no warranties this works for you / at your own risk).

Strangely the M2 nvme drive speed was affected in some of the runs, with 3600 & 3800 passes being the exceptions.
If anyone has ideas to why or what to adjust to get more consistent speed from M2 nvme across testing. I would be very interested.

Did not bother with certified 4100 @ 4133 DOCP profiles or faster clocks, maybe in the future.

Hope this might be of help to the more adventurous of us.

I checked the nvme passes with two different benchmarks at various speed tested above and they both show a normal linear growth with speed increases along with the RAM.

Not sure why userbench is showing what it does, but it does throw the scoring out as well (no other benchmark program captures the userbench shown nvme scaling with ram issue). Strange issue, I noticed it while ago but never checked till today. I wonder if this effects Intel and other amd systems ?

Level 10
Neo ram is still broken for this calculator. If you click the XMP button is does nothing for reading the ram at all. I did a good bit of Google searching and everyone that has this new ram has the same exact problem with it? It will not read their ram timings and leaves it blank. I guess I can purchase some different model ram and see how that goes. I sent the maker of the Calculator an email but never got a response back. If anyone has another idea let me know. It seems my options aren't very good right now.