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RAM Tuning - Help with subtimings.

Sorry to jump on a thread, but as there's talk about micron e, can't help it.
My 3600 isn't stable at anything beyond 1866 FCLK.
As I said, 2x8 is fine w/e I throw at it, but 4x8 is a problem I can't seem to solve.
Apart from trying to raise SOC and DRAM voltages, maybe try running 2T, is there anything else I'm missing from the big picture? I'm well aware not to expect anything from a daizy chain topology and 4 sticks, but is there a way to make it work without shooting above 70ns latency?
The issue may not your board or its daisy chain topology it's more likely your CPU or IMC.

Your B450 Tomahawk has the same Topology and RAM OC capabilities has my B450M Mortar Max.
I did 1967 FCLK with 4 X Mircon Rev.E SR dimms but this was using ZEN 3 which has a better IMC. Your setup should boot all 4 X dimms with XMP 3200 CL16 with GDM enabled 1T.

Try setting your ProcODT to 43.6 and increase VDIMM to 1.45V and see if you can boot then. VSOC should be between 1.10V to 1.15V. Latency will increase but the benfit of a Dual Rank setup more than makes up for it. You will get higher 1% lows and better overall fps in games with a DR setup.
C9BLM 3933 CL16 TM5 PASS CROP.jpg


 
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it's more likely your CPU or IMC.
Probably. It will be replaced by 5800X3D or 5700X, 5800X soon anyway. I got the second 2x8 kit mostly for the 4K upgrade I'm slowly transitioning to. So only two pieces of a puzzle left, the CPU and the display. I hope the upgraded CPU will be able to work with at least 1900 FCLK. BTW the boost algorithm never worked for my 3600, PBO and such was a letdown. It doesn't shine in the static OC neither, but it's the only way to make it work past 4.1GHz. Tried most of the AGESAs from the beginning with no luck (1206c ATM, and now I see they've added 1208 few days ago, but it's a beta), and I'm kinda afraid not being able to tweak anything for the 5800X3D.

Try setting your ProcODT to 43.6 and increase VDIMM to 1.45V and see if you can boot then. VSOC should be between 1.10V to 1.15V
I'll try thank you. Booting was never an issue, but it would BSOD randomly on idle whatever I tried, apart from stock timings.
 
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So the secret to running 1usmus seems to be giving more memory to Windows. I gave Windows 1024MB reserved instead of 512 or 256 (latter being the default) and I managed to run it for hours on end.

I got no errors on it, though. I did relax some secondaries and it might've done it.

1680010389928.png
 
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So the secret to running 1usmus seems to be giving more memory to Windows. I gave Windows 1024MB reserved instead of 512 or 256 (latter being the default) and I managed to run it for hours on end.

I got no errors on it, though. I did relax some secondaries and it might've done it.

View attachment 289582
Update: I had to bring tCL back to 18 eventually, as it failed a 24-hour test. Subsequent runs with tCL 18 ran fine for as long as I could muster my patience, so about a day and a half. Was busy for most of the rest of the year though, so I didn't have time to play with it more.

1700769460259.png


Current timings. Worth playing with anything to get tCL back to 16?

tPHYRDL is still not the same for both sticks, ProcODT made no difference.
 
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Since we're not sure on the chips (Micron rev E?), these are just approx guides. Start with changing one line at a time as written below.

tRC try 61 (tRC=tRAS+tRP), increase slightly if unstable. If one of those values don't follow the formula, they will be autocorrected to the higher value that satisfies the formula.
tRRDS/tRRDL/tFAW 6/8/24, if that works, try 4/6/16 as well (probably won't).
tWTRS/tWTRL 4/12
tWR/tRTP 16/8 (tWR=2*tRTP, but not absolutely necessary)
tRFC will depend on what chip it is, try slightly below 600 (550-590 for ex.).
*SCL to 4 (both)
tRDWR 10, increase if unstable
tWRRD 3
Tertiary:
View attachment 286059

GDM disabled 2T will allow you to run odd tCL, up to you if you want to try it.

Also, check tPHYRDL values if they are the same 26/26 on both sticks (drop down menu in ZenTimings). They should be the same for your config, but just make sure.
Any suggestions to my settings?
1700771559177.png
 
Current timings. Worth playing with anything to get tCL back to 16?
Not really, looks ok to me.

Any suggestions to my settings?
Looks good too. Have you tried lowering VDDP voltage to ~900mV? Any chance of running it GDM off and 1T? (probably need to set AddrCmdSetup)
Is *SCL 2 faster for you than SCL 3 or 4? There are various reports of 4 being more optimal in some cases.
 
Not really, looks ok to me.


Looks good too. Have you tried lowering VDDP voltage to ~900mV? Any chance of running it GDM off and 1T? (probably need to set AddrCmdSetup)
Is *SCL 2 faster for you than SCL 3 or 4? There are various reports of 4 being more optimal in some cases.
Will give it a work over

GDM off gave some issues in windows - what do I have to set at AddrCmdSetup? Setting 1T manual didnt help much (apperently it can be set two places in my bios) I have som adressing error in crome with these settings. The SCL settings and the VDDP is a result of listening to several Buildzoid rants. Thanks for input

Have some vacation time the rest of the year so have time for tinkering :-)
 
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Will give it a work over

GDM off gave some issues in windows - what do I have to set at AddrCmdSetup? Setting 1T manual didnt help much (apperently it can be set two places in my bios) I have som adressing error in crome with these settings. The SCL settings and the VDDP is a result of listening to several Buildzoid rants. Thanks for input

Have some vacation time the rest of the year so have time for tinkering :)
AddrCmdSetup 56 is usually the first value to try and stabilize 1T GDM off, but it's not a big difference either way, just to see what the setup is capable of.
 
1700775338248.png

Sorry for my noob ignorance but is it the 20ohm setting you will change from 20 to 56?

My ProOCDT 40omh and the 20omh setting is grabbed from one of the Builzoid rants

Had a hard Bluescreen in windows and got corrupted bootfiles in windows so turned Geardown mode on again but will try it if the 40/20ohm values can help does they need to be in sync so the ProcODT is double to the others? The next value above 40 is 60 on my board and the nex again is 80.
 
Sorry for my noob ignorance but is it the 20ohm setting you will change from 20 to 56?
No, the segment below *DrvStr, AddrCmdSetup is 0 currently.
 
CadBus.jpg

Found the CAD Bus timings in another part of my bios but it seems that values is in hex? (not my strong point)
 
Try DrvStr 40 20 30 20, that may fix 1t gdm off, but usually it is very hard getting gdm off 1t working with 4 sticks.
 
In the other menue I have these settings
Mem 3.jpg

Taraquin@ is it these you would change from 20ohm to 40 20 30 20? And what about ProcODT should I raise it as well?
 
In the other menue I have these settings
View attachment 322785
Taraquin@ is it these you would change from 20ohm to 40 20 30 20? And what about ProcODT should I raise it as well?
In unrelated news, how did you take a picture of the UEFI?
 
View attachment 322783
Sorry for my noob ignorance but is it the 20ohm setting you will change from 20 to 56?

My ProOCDT 40omh and the 20omh setting is grabbed from one of the Builzoid rants

Had a hard Bluescreen in windows and got corrupted bootfiles in windows so turned Geardown mode on again but will try it if the 40/20ohm values can help does they need to be in sync so the ProcODT is double to the others? The next value above 40 is 60 on my board and the nex again is 80.
Here are some examples of GDM disabled Real 1T VS using ACS 56. Has already pointed out by @Taraquin with 4 Dimms is much harder to get stable than with 2.
This being said it will be much easier to stabilize TCL 15 VS 14 and you would probably use much less voltage in the process.

3800 CL15 GDM Disabled Real 1T
PV4133 3800 CL15 1T R 25C 2023.jpg


3800 CL14 GDM 1T disabled using ACS 56
PV4400 3800 CL14s Tm5  Pass 1.5V crop 2023.jpg


4067 CL15 GDM disabled 1T using ACS 56
PV4400 CL15 4067 155V TM5 Pass 2023.jpg


In unrelated news, how did you take a picture of the UEFI?
There is usually a hotkey to take screenshots F12 I believe in most cases. It may be different depending on mobo BIOS or vendor.
 
In unrelated news, how did you take a picture of the UEFI?
Im using F12 and have a USB stick permantly connected inside my case via an adapter (https://www.av-cables.dk/usb-pin-he...MI8caA0LncggMVo5WDBx0omwKdEAQYDyABEgLRZvD_BwE) so I can save my profiles and pictures of my settings for when I upgrade the bios to a newer revision. E.g. when I updated from F36f version to F37g. I first saved a profile to the USB stick and then saved the pictures of the settings to. Haveing the profile and all the bios versions at hand allows me to make a rollback with the same settings if a new bios dosent work out. Im using this setup in all of my builds for several years as well as when Im building for others. In fact I have an extra USB 16+GB stick in there for installing windows and drivers.

Thanks to all for your input will do some tinkering
 
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