You seem to have shown that both DIMMs work OK when a single stick is inserted into either socket. I infer from this that both memory channels in the CPU are working (in isolation) and the PCB traces from the CPU to both DIMM sockets are OK. However, the computer becomes unstable when the system switches from Single Channel to Dual Channel mode with both DIMMs installed.
I've seen a note saying the Ryzen 2600 can only reach 2933MT/s on a mobo with a high quality 6-layer PCB (and only 2 DIMMs) but i suspect your motherboard may be only 4-layer with fewer screening planes. You've already shown the system remains unstable with 2 DIMMs at 2400MT/s, but a 4-layer PCB might explain why the PC doesn't boot at 2800MT/s.
I don't know what pcb layers my mobo has, how to check it...
A quick check on the web reveals that early Ryzen chips were fussy about RAM. Do you know if your memory on the QVL (Qualified Vendors List) for the Asus Prime A320M-F? I don't usually worry when my RAM isn't mentioned in the motherboard's QVL and have been lucky so far.
I looked at QVL list and there is not support for the exact my ram's 2666mhz versions. In details, my ram part.no is PSD48G266681, it is not in the list. There is similar with 2400mhz version which supports 2 socket dimm. So in theory (and practice) this maybe the reason why dual channel doesn't work well!? I'm attaching the list pdf you can also view. Btw, if I buy new rams, which brand would you advise for higher frequencies (which is supported by my mobo and cpu)?
Do you have the latest BIOS installed, Version 6042 or Version 6061 Beta? I'm not sure if I'd use the Beta version, but if your BIOS is earlier than 6042, it might be worth updating to see if it improves stability.
Yes, I have 6042 bios and also don't want to upgrade to beta (if at all).
I notice you've had problems with a second-hand RV570 which may have been used in crypto mining. I get the impression the system is still unstable when you use another (non-gaming?) graphics card, but it's slightly more stable than the RV570. I'd be inclined to continue testing without the RV570, even if you've successfully flashed its mining BIOS back to standard. It's possible the RV570 may have been stressed/damaged by mining and is now affecting the stability of the PSU and hence the CPU's supply. This is only a guess on my part. I'm starting to "clutch at straws". I don't know the 1st Player 700W PSU. Is it a high quality device?
Yes, this was another big problem and I think I solved it successfully with the helpful guys there but now in conjunction with this problem not sure. You know how it is: I have my folder where I keep about 4gb vids. If I enter that folder and set view size to - large or even medium, PC restarts immediately on every try only when I have both ram set, if I have only 1 ram set, then it doesn't restart. I removed this "new" RX 570 and put my old Nvidia card with both ram set and tried to enlarge video icons again and guess what - it does not restarted. So now logically this means that RX 570 makes it but I remember when building PC I also had random restarts but then I haven't yet bought RX 570 and was using my old Nvidia card. All this is very confusing now, I will continue to test with old Nvidia card and also can replace my new ssd with an old hdd to test it too. Btw temperatures on all parts are normal even in a graphics intensive game, I often monitor them.
I don't know the 1st Player 700W PSU. Is it a high quality device?
I bought that Psu new. I also don't know is 1st player high quality brand or not and how to check that.
Well some interesting posts I found in internet:
1. When I was searching for "unexpected procedure from cpu", I found this post:
https://github.com/memtest86plus/memtest86plus/issues/180
One of the responses there is: "Ah, looking at the screenshot, your XHCI controller is mapped above the 4GB boundary. Please could you test the fix I've just pushed" and then the author of the post replies: "Yes that worked perfectly, and it's now doing the memtest, thanks!"... I don't know if this could be important and how can I also check this in my Bios.
2. I wanted to run Gpu stress test with Aida64 and when I pressed the checkbox it show this window:
I Searched for Video Driver timeout and found some articles where they say that this should be set to 8. This is one of them:
https://www.nvidia.com/en-us/geforc...ards/5/508243/timeout-detection-and-recovery/
"Timeout Detection and Recovery set to low could mean that something has set the TDR or correlating values below their defaults. TDR should be at 8 Use Wagnard TDR Manipulator to make sure these are at Default."
I downloaded TDR Manipulator and it shows - 2 as Windows default. I'm not sure why that guy (Greybear) says it should be set at - 8. Well, maybe, when I flashed the bios of VC and if that bios was incorrect, then I also might have wrong driver for my card and maybe that's why it's not set to 8 and since I get restarts when entering video (only) folder and video is related to VC, then wrong TDR value might trigger restarts and this also explains why I don't have that with my old Nvidia card. But all these are just my guesses.
UPDATE: I tested with old card and hdd and still have restarts. So Video card shouldn't be related.
On the other hand, if it is bad cpu or motherboard, why would they work well on 1 ram module?!