[SOLVED] Ryzen 3900xt and Viper 4400mhz (need help)

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93boba

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Hello!

Until recently I was able to run my memory on 4200mhz with the XMP profile. After updating bios and drives I am no longer able to.
My memory is running at 2300mhz which is pretty low.

I got informed that 4200mhz is overkill and that the optimal RAM frequency for Ryzen 3900XT should be 3600mhz.
My XMP profiles are only 4400 and 4200.

How can I manually set the RAM freq to 3600mhz?

I'd appreciate it if any expert is willing to tell me how to underclock Viper Steel 4400mhz to 3600mhz.



Processor AMD Ryzen 9 3900XT 12-Core Processor 3.80 GHz
Installed RAM 16.0 GB (Viper 4400mhz) (2x8GB/2A-2B)
System type 64-bit operating system, x64-based processor
Mobo Aours Master x570
Graphics 2080 OC
PSU Cooler Master 750w Gold (or platinum)

Edition Windows 11 Pro
Version 21H2
Installed on ‎30-‎Jun-‎21
OS build 22000.258
Experience Windows Feature Experience Pack 1000.22000.258.0


Benchmark (Before drivers/bios update):
https://www.userbenchmark.com/UserRun/36260233

Benchmark from today(unstable, rebooting system):
https://www.userbenchmark.com/UserRun/47265434
 
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Solution
Okay here are the final results:

1# 3466Mhz/ 15 15 15 36 / 1.2V (Stable)
2# XMP 4266Mhz/ + High-Frequency Support Level 2/ 1.35V (Stable)
3# XMP 4400Mhz/ + High-Frequency Support Level 2 / 1.45V (Stable)
4400mhz UBM

4# 3600Mhz/1800FCLK/ 15-15-15-26 /1.35V (Stable)
3600Mhz UBM

5# 3800Mhz/1900FCLK/ 15-15-15-26 /1.37V (Stable)
3800Mhz UBM

mamasan2000

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I was able to run stable 3466mhz at stock settings. Whenever I change the timings system reboots eventually.
Benchmark
Any BSOD? Do you know if your PC is stable at 3600 Mhz with other RAM? Is your Fclock able to run 1800 Mhz and not cause any WHEA 19 errors? Hwinfo64 should show those. Event viewer does too, if you filter the log.
UserBenchmark doesn't tell me anything. It is all over the place. Only thing it is good for is components of your system, if you don't know what you have. But even then, there are other programs.
 

93boba

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Any BSOD? Do you know if your PC is stable at 3600 Mhz with other RAM? Is your Fclock able to run 1800 Mhz and not cause any WHEA 19 errors? Hwinfo64 should show those. Event viewer does too, if you filter the log.
UserBenchmark doesn't tell me anything. It is all over the place. Only thing it is good for is components of your system, if you don't know what you have. But even then, there are other programs.

Never had BSOD on this PC. 3600mhz is the sweet spot for Ryzen 9 and 1800mhz Fclock is ideal recommended by AMD.
INFO
 

mamasan2000

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Never had BSOD on this PC. 3600mhz is the sweet spot for Ryzen 9 and 1800mhz Fclock is ideal recommended by AMD.
INFO
Sounds like the company line. Imagine us being on a steamtrain, in the front, driving the train. The train comes to a sudden unexpected halt and I ask you: "Why are we stopping? Did you check that we have enough coal burning? Did you check that we are not overheating?". And your answer is: "This Northern Traveler line of trains can do 80 km/h when the wind is in the back. It is in their commercials".
Yes, yes, it can. But currently, we are not moving at all. We are stuck here unless you check exactly why the train stopped.
 

93boba

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Okay here are the final results:

1# 3466Mhz/ 15 15 15 36 / 1.2V (Stable)
2# XMP 4266Mhz/ + High-Frequency Support Level 2/ 1.35V (Stable)
3# XMP 4400Mhz/ + High-Frequency Support Level 2 / 1.45V (Stable)
4400mhz UBM

4# 3600Mhz/1800FCLK/ 15-15-15-26 /1.35V (Stable)
3600Mhz UBM

5# 3800Mhz/1900FCLK/ 15-15-15-26 /1.37V (Stable)
3800Mhz UBM
 
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Solution