Question GB X570 Aorus Master w/ Ryzen 3900X doesn't post in DUAL channel mode

[Roland30]

Hello everyone,

In my new config(I've built it a month ago...) , I sadly experience after a simple reboot something is not okay. I checked, and it has turned out that the DIMM slots don't work properly. I've tried all the slots each by each and got always an error code C5 (reserved code) . Only the A1 slot working. Neither of any remaining slot works, nor in single channel mode, nor in A1B1 / A2B2.
What could happen to a DIMM slot that causes such a trouble like this in case of a high-end MOBO ?

What makes me think is that, everything was going well with this setup & specs below so far... and can't even imagine what could have happened........

SPECS:
Mobo: Gigabyte Aorus X570 Master w/ BIOS F7b
CPU : AMD Ryzen 9 3900X
VGA: EVGA RTX 2080 Ti FTW3 Ultra
RAM: 4*8 GB HyperX Predator 3200 C16
AIO: NZXT Kraken X62
SSD(sys) : NVMe M2 Samsung 970 Evo Pro
PSU: Corsair TX 750M

With the latest W10 and all the drivers updated including Ryzen Master, chipset drivers from the official webpage, etc.

What I've tried so far:

• plug & unplug all the cords, each components
• reseating all the DIMM slots
• reseating the CPU and the AIO
• flashing the BIOS back to the F6, F5, F4 (stock)
• clear the CMOS

I think all the existing methods have been tried with no result. Now I'm running with that one 8 GB module, and all the values are normal... checked in several monitoring tools.

What do you recommend guys?

 

[Lutfij]

Remove the CMOS battery for 15 mins, while the desktop is disconnected from the wall outlet, then replace the battery. See if that helps. If all sticks of ram work on the one slot on the board but not on any other board, while you're on the latest BIOS(F7b and on F6, don't downgrade any further) then it's likely the board has faulty DIMM's.

 

[Roland30]

Remove the CMOS battery for 15 mins, while the desktop is disconnected from the wall outlet, then replace the battery. See if that helps. If all sticks of ram work on the one slot on the board but not on any other board, while you're on the latest BIOS(F7b and on F6, don't downgrade any further) then it's likely the board has faulty DIMM's.

I've tried it , but nothing has changed. Apart from this, thanks m8! I'm gonna send it to RMA 2morro.

This post will be kept updated, as I see not too many people having this kind of error code, and also seeing unfortunately there are quite a lot of issues with the new X570 & Bios versions when it comes about the Ryzen 3rd Gen.