Attempted to tighten timings via DRAM Calculator, unsuccessful

VirtualMirage

Limp Gawd
Joined
Nov 29, 2011
Messages
470
So after going back and forth as to whether I wanted to try and tighten the timings on my DRAM while keeping its speed the same (3600MHz), I decided over the weekend to make the attempt using the SAFE settings for my RAM. Boy, that was a failure! Computer wouldn't even boot. Thinking maybe I just needed to up the RAM voltage a little (it originally recommended leaving it at 1.35v), I upped it to 1.37v and tried again but still nothing. Ended up having to reset my BIOS settings via my CMOS reset button on the board to be able to get back into the menu. Not quite sure what went wrong.

My RAM is the following:
G.Skill F4-3600C16D-32GTZN (2x16GB)
16-16-16-36 at 1.35v

My Motherboard/CPU is the following:
Asus Crosshair VIII Impact with a Ryzen 9 3900XT CPU

I pulled my RAM info from Thaiphoon, imported the XMP data from it into the Ryzen DRAM Calculator 1.7.3, selected my 3600 for my frequency, then chose Calculate Safe. I then went into my BIOS, wrote down all the settings it was currently configured for, then proceeded to make the changes as described on the main page, advanced page, and power supply system in the DRAM calculator. On the main page, I was able to find everything to change except for the BGS values. On the Advanced page, I made the changes found under Main Voltages and CAD_BUS Timings. Under the Power Supply System, I made the changes found under the VDDSOC for Best CPU/DRAM stability. My CPU settings for power were already configured from before to what was recommend for the Clock Tuner for Ryzen app, so I left that alone.

Here are the settings DRAM Calculator recommended and what I tried to apply:
DRAM_Calc_Main.PNGDRAM_Calc_Advanced.PNGDRAM_Calc_Power.PNG

Here are the auto settings my motherboard sets based on the XMP (DOCS?) profile of the RAM:
Capture.PNG

Ignore the core voltage at the top. I captured this right after a system reboot and the voltage was bouncing around as tasks were loading in the background, so CPU speed and voltage were still stock/auto and my overclock settings that use a fixed clock rate and lower voltage were not applied yet.

Am I missing something? Is it just not doable?
 
I need 1.4v minimum on my bdie to boot the safe settings and closer to 1.44v for rock solid.
 
Bdie can run 1.5 without breaking a sweat but some extra air over your ram is recommended if you go over 1.45
 
The dram calculator worked great for my ram. I got 1900 (3800) stable, but not with a 1900 infinity fabric. The safe settings seemed to do the trick nicely for a 1:1:1. Sadly, I got no gain from PBO with the dram recommended/if/cpu settings it recommended so have left my cpu stock.
 
The dram calculator worked great for my ram. I got 1900 (3800) stable, but not with a 1900 infinity fabric. The safe settings seemed to do the trick nicely for a 1:1:1. Sadly, I got no gain from PBO with the dram recommended/if/cpu settings it recommended so have left my cpu stock.

I can get 1866 IF to work on my 3950x, and the 5000 series is supposed to be a bit better, but its still luck of the silicon lottery draw to a large extent. I am thinking you might want to try again after a few bios updates have come out as you might just be able to get that 1900 IF at some point if you are lucky.
 
So...do you think that my numbers and settings are fine with exception to just the RAM voltage and that needs to be increased? To what? 1.4v, 1.45v? The max the calculator mentioned for Safe is 1.4v. Are there any other settings I should be concerning myself with?

I want to keep the 1:1 IF ratio and also I don't want my PCIE Gen4 to kick down, I thought I read somewhere that going too high out of spec can cause PCIE to kick down to Gen3. Since both my video card and M.2s take advantage of Gen4, I'd like to keep it within the acceptable range. As such, I was fine with keeping my speeds at DDR3600, I just wanted to optimize my timings and improve latency.
 
So...do you think that my numbers and settings are fine with exception to just the RAM voltage and that needs to be increased? To what? 1.4v, 1.45v? The max the calculator mentioned for Safe is 1.4v. Are there any other settings I should be concerning myself with?

I want to keep the 1:1 IF ratio and also I don't want my PCIE Gen4 to kick down, I thought I read somewhere that going too high out of spec can cause PCIE to kick down to Gen3. Since both my video card and M.2s take advantage of Gen4, I'd like to keep it within the acceptable range. As such, I was fine with keeping my speeds at DDR3600, I just wanted to optimize my timings and improve latency.
Yeah the IF is automatically 1/1 up to 3600 but after that it will automatically initiate doing a divider if you leave it to do so and simply increase the speed (could be after 3733?) BUT you can go into the advanced AMD overclocking and manually set a higher infinity fabric at half your ram speed to keep the 1/1 ratio for example IF at 1900 with 3800 ram speed. Thing is most chips don't like going higher than 1800 IF. As for your setting everything seemed fine, I am suggesting that yes you should not be afraid of putting more dram voltage than what you are trying at 1.375. 1.4 is what they list as the "max" but there are plenty of Bdie kits that come from the factory at higher levels even up to 1.5 stock. I would start with 1.4 and see how it boots. If like me this allow you to post then you are making progress and you might only need that to be fully stable. If its stable then maybe you can go back down a notch or two. If it posts but ends up crashing somewhere later in the boot cycle or gives errors or crashes with programs I personally think its perfectly safe to go a bit higher such as 1.45V if that is what you need to make it perfectly stable.
 
I don't know anything about the PCIX issue you mentioned, but no harm / foul keeping it at 3600 and just going for really tight timings.
 
16GB sets are little harder to set, and this calculator is not always correct ;)
Also about voltages, my b-die set has two XMP profiles, one for 1,35V the other for 1.45V stock, so up to 1.45V if the cooling is ok you should be good. Besides errors caused by overheating are usually easy to spot (it starts to throw errors in TM5 after ~30 minutes of operations, hardly ever before that).
edit: last thing, even when you take settings from calculator, apply them in steps/groups, otherwise it'll be harder to figure out which one is causing instability (especially if it's minor one, allowing you to boot but then throwing errors in memory test, or occasional blue screen). but for that you need to learn which settings are connected, and which can be applied individually
 
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I would suggest getting a proper read out of your memory using Thaiphoon tool. Update the data in the ryzen dram tool and see if it still gives the same recommendations. I would also make note of the settings in the Power Supply System Tab when adjusting settings to better stabilize the settings.

I took a few shots at 1933 with some soc tweaking

I can report that I got 3866 working! Cyberpunk 2077 got a 1-2 fps boost so I'm holding 70s in the worst outdoor areas full of people @ 1440p ultra rt dlss quality

1607982127019.png
 
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I would suggest getting a proper read out of your memory using Thaiphoon tool. Update the data in the ryzen dram tool and see if it still gives the same recommendations. I would also make note of the settings in the Power Supply System Tab when adjusting settings to better stabilize the settings.

I took a few shots at 1933 with some soc tweaking

I can report that I got 3866 working! Cyberpunk 2077 got a 1-2 fps boost so I'm holding 70s in the worst outdoor areas full of people @ 1440p ultra rt dlss quality

View attachment 309120
I did use the Thaiphoon tool to read the RAM. I then exported that into a report file to import into the calculator and what you see above are the results it suggested. I also made adjustments for the VDDSOC based on the recommendations in the Power Supply tab. I just didn’t adjust the CPU to those settings because I had already previously made changes to it earlier when overclocking the CPU.
 
To get mine stable at my settings, I had to omit using the final recommendations on the first page for CAD_BUS. I left mine at auto. Manually changing those settings caused windows to load in with corrupted graphics.
 
To get mine stable at my settings, I had to omit using the final recommendations on the first page for CAD_BUS. I left mine at auto. Manually changing those settings caused windows to load in with corrupted graphics.
yea that's good idea, CAD_BUS you need to touch when you try to disable GMD mode, for most other cases it's better on auto
 
I had a similar experience with the DRAM calculator on a pair of 3200CL14 b-die sticks and a 2700X. Using SAFE and some of the alternate resistance settings (I forget which ones, it was over a year ago) I could get it to boot at 3200 but it wasn't stable. I ended up back at default BIOS settings and clocking at 3133 MT/s instead of 3200, and it's rock stable (as in 43 days uptime at the moment). I don't doubt that I could tweak it up, but stability is more important on this rig than taking a few seconds off of a 10 minute build.

The DRAM calculator seems to work like magic for some, not so much for others. You just have to play with it, if you have the time.
 
go with the max dram & soc voltages. (soc 1.1 & dram 1.4 on your screenshot) can even go up to 1.45 on your ram since all DDR4 is suppose to be able to handle that per JEDEC specifications.
 
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