I'm a PITA I know but I did further testing
I tried a CMOS reset and default settings (only DOCP enabled for XMP profile 3600 CL16).
Cinebench results were much lower: 6853 multi, 489 single.
I stand my position: the motherboard is giving too much voltage and it affects temperature (
in my situation of cooler and ambient temperature).
I monitored Voltage and clock speed, and it was around 4.3 GHz single core and 3.9 GHz multi, while temp was hitting 82º (in multicore) before settling down at 80º. Voltage initially was 1.27 V (single) and 1.38 V (multi).
With a -0.075 V undervolt the situation was much better.
Cinebench results: 7188 multi, 507 single (consistent).
Clock speed was 4.5 GHz single (this alone is very important IMHO. I'm almost reaching the max rated freq, which indicates the CPU is working within limits) and 4.1 GHz multi (almost 200 MHz more than default voltage). Temperature never exceeded 80º, settling down at 78º (multicore).
I observed the voltage and it was 1.25 (single) and 1.35 V (multi).
As far as I can see temperature is the culprit here.
Without undervolting I'm hitting temperature limits that starts throttling back voltage and thus frequency in order to keep the CPU below 80º.
With undervolting I'm giving my CPU a little thermal headroom to reach slightly higher clock speeds (about 100/150 MHz).
I'm curious about results with a 8/10º lower ambient temperature.
A better air cooler (Noctua D15) or a custom loop liquid cooler could improve the situation, for sure, but considering the high cost involved and the very little improvement I'm not planning to do that
Mine is a 3700X......if your 3900X can barely match mine in ST and sports a nearly 0.2GHz single core deficit at stock compared to what is advertised, then something's blatantly wrong with your BIOS settings or board itself. Matisse not meeting advertised box speeds was completely fixed about 8 months ago...
Clear CMOS and start fresh, see if anything changes. Make sure your chipset drivers are up to date from AMD's website.
Half of the reviews you linked are launch day reviews. Like I said, early AGESA prior to 1.0.0.3ABBA had serious boosting issues, leading to the whole commotion about "Ryzen not meeting advertised speeds". Today, all reviewers are standardized on 1.0.0.4B or v2 and there is, firmly, no way a 3900X scoring below 510 stock is "normal". Notice the results for all the Matisse CPUs:
View attachment 165278
As to your cooler, I have no doubt you would see higher all-core clocks under water, but it's not the culprit behind your single core clocks.
do you want me to say YOU ARE RIGHT ?
The Techpowerup review you reported above is FROM 1 JULY 2019
Exactly like the others.
BTW I will help you: I found a more recent review , one from July 2020 :
The result is above 510, ok, but we are speaking about a "whole"
11 points, or 2% difference.
I wouldn't speak about "something's blatantly wrong"
, especially because they are using a
Gigabyte X570 Aorus Master motherboard with 8GB G.Skill FlareX CL14 modules for a 32GB capacity, so the 11 points difference could just be caused by a better system (the cooler was not specified but they usually are using Corsair Hydro H115i RGB Platinum 280mm liquid cooler).
BTW temperature are lower this evening (due to a thunderstorm ) and take a look:
the CPU reached the rated 4.6 GHz during the test
this with a -0.075 V of undervolt.
It was an ambient temperature related "issue".
Tamb is 24º now. It will further improve.
Just to add more data, this review with AGESA 1.0.0.4 has a whole 4 points difference from my CPU in single (and a lower result in multi !). Are you still speaking about "something blatantly wrong" in my setup ?
I just think something is blatantly wrong in the Dutch weather this summer