Test 8 fails when matching clock speed with FLCK

[devildaggers]

Hello. First of all, thanks for the tool.
English is not my first language so bear with me.

My specs:
Ryzen 7 5800x
Asrock B450M Steel Legend (last update, 4.60).
Kit with troubles: Kingston Fury Renegade 16GB 3600MHz DDR4 CL16 KF436C16RB1/16
Old kit that works: XPG Gammix D30, 8GB, 3200MHz, DDR4, CL16 - AX4U320038G16A-SB30

I recently bought two new RAMs and have been having troubles for the past few days.
The kits show multiple fails at test 8 when matching ram frequency and FLCK. Like 3600/1800 and 3200/1600.
I tried increasing voltage until 1.5v on the kits, and the erros just increase. Also tried increasing SoC voltage (starting at 1.150 till 1.3 I guess) and those VDDG stuff, but the errors woudn't go away.
I pulled up my old rams and tested 3600/1800, stock XMP configuration, and everything ran great.
When I tried putting 3600/1800 and everything on Auto, the BIOS wouldn't post, reset itself and then post.
Right now I'm running the kits with 3600/1766 lol. Ran some testes with LatencyMon and WhySoSlow, and everything came back fine. I will probably RMA these kits, but is there a chance my CPU or MOBO can't handle dual rank high speed kits?
I'm not a overclock maniac, just followed stuff on google and tried. Read somewhere about the 2:1 ratio and been using it.

Thanks in advance and sorry about any errors. It's been a hot minute since I typed anything in english.

[David (PassMark)]

If you believe the AMD product page for this CPU, then the Ryzen-7-5800x can only support 3200Mhz DDR4 RAM. (And I assume they mean 3200MT/sec and not really "Mhz").
https://www.amd.com/en/products/cpu/amd-ryzen-7-5800x

A quick search of the internet shows many people have it working at 3600MT/sec however. But I also found a bunch of people having problems at this speed. So it seems this just good luck combined with a good set of RAM sticks and not a 100% guarantee?

[devildaggers]

I also came to the same conclusion, Maybe it is fine at 3600 8gb but not at 16gb (per kit)?
My 8gb kit is Micron and the 16gb one is Hynix, don't know if there something like memory controller compatibility.
However, I will test the faulty kits at a friend's house (same mobo, ryzen 5 3600) and gather some evidence.
Will update here before sunday.

But... have you seen something like my issue?
Thanks for your help and for the input! I took a look around and you guys run a great forum.

[David (PassMark)]

We don't have this exact CPU. But running RAM/CPU above the spec'ed clock speed will often cause problems.
(I mean if it was always stable at a faster speed the manufacturer would have sold it at a higher speed and charged more in the first place)

[devildaggers]

We don't have this exact CPU. But running RAM/CPU above the spec'ed clock speed will often cause problems.
(I mean if it was always stable at a faster speed the manufacturer would have sold it at a higher speed and charged more in the first place)

Hi. Could you please lock this thread? I ended up RMAing the rams without testing on my friend's pc.
Thanks for the help and for keeping this project up.
Much love.