Asus ROG Crosshair VIII Dark Hero - Memory from QVL - D.O.C.P. Standard - The system has POSTed in safe mode

Question

I have just built my new computer with Asus ROG Crosshair VIII Dark Hero motherboard, AMD Ryzen 9 5950X CPU and Corsair Dominator Platinum RGB Black DDR4 3600MHz 4x16GB - CMT64GX4M4Z3600C16 (Ver4.31) memory.

On a previous build a few years back I made the mistake of not looking at the memory QVL before buying my memory sticks and then tried to load XMP profile.

XMP causing POST safe mode - ASUS ROG STRIX Z370-F Gaming

This time I was not going to do the same mistake so I ordered memory that is made to work with Ryzen™ 5000 Series CPU:

Memory QVL for AMD Ryzen™ 5000 Series Processors_X570-4DIMM

https://rog.asus.com/us/motherboards/rog-crosshair/rog-crosshair-viii-dark-hero-model/helpdesk_qvl

https://dlcdnets.asus.com/pub/ASUS/mb/SocketAM4/ROG_CROSSHAIR-VIII-HERO_WI-FI/Memory_QVL_for_AMD_Ryzen_5000_X570-4DIMM.pdf

I also checked that the CPU I ordered was in the CPU support list which it is.

Ryzen 9 5950X (Vermeer) (3.4GHz,105W,L3:64M,16C)

https://rog.asus.com/us/motherboards/rog-crosshair/rog-crosshair-viii-dark-hero-model/helpdesk_cpu

Looking at the QVL it says this:

Vendors
CORSAIR 

Part No.
CMT64GX4M4Z3600C16(Ver4.31) 

Size
4x 16GB 

SS/DS
DS

Timing
16-18-18-36 

Voltage
1.35

DIMM socket support (Optional)
1 DIMM 2 DIMM 4 DIMM

Since I want to use 64GB I have every DIMM inserted.

Setting the D.O.C.P. Standard under Extreme Tweaker -> Ai Overclock Tuner sets the correct values when looking at timings above.

However this causes the following error:

The motherboard had BIOS version 3204 installed when delivered but I have also tried with 3302, 3401 and 3501 Beta. The same thing happens every time.

https://rog.asus.com/us/motherboards/rog-crosshair/rog-crosshair-viii-dark-hero-model/helpdesk_bios

Running D.O.C.P. Standard but changing Memory Frequency to DDR4-3333MHz instead of DDR4-3600MHz causes the system to boot but I don't know if it is stable or not yet there.

Have I missed something or is something wrong with the components?

I took a photo after applying thermal paste to the CPU that confirms the memory is correct part no, version and timing:

Complete computer specification:

• ASUS GeForce RTX 3090 ROG STRIX OC - 24GB GDDR6X RAM
• Corsair AX1000 V2 80+ Titanium 1000W
• AMD Ryzen 9 5950X with Noctua NH-D15
• ASUS ROG Crosshair VIII Dark Hero
• Samsung 980 Pro Series MZ-V8P2T0BW 2TB
• Corsair Dominator Platinum RGB Black DDR4 3600MHz 4x16GB - CMT64GX4M4Z3600C16 (Ver4.31)
• Fractal Design Define 7

Answer 1

Try to rule out the CPU/IMC by lowering the DDR Frequency and Infinity fabric clock to 3400/1700 respectively. I have this issue at IF clocks of 3800 or higher because my 5900x has a crappy IMC. I've never heard of one not being able to do 3600, however.

Answer 2

Thanks to @butt_yodel for pointing me in the right direction!

Setting FCLK Frequency to 1700MHz allowed me to run the memories at DDR4-3466MHz.

On Reddit I saw the comment Fclk = half memory speed.

https://www.reddit.com/r/Amd/comments/jxaj4m/what_is_the_default_fclk_for_a_5950x/

Since I tried to run DDR4-3600MHz I had to set FCLK Frequency to 1800MHz.

After doing this the computer booted fine!

Answer 3

Am4 boards ram runs cold. Crank it up to 4000ghz and bump the voltage up. Xmp puts it's at 1.35v and that's pretty low. 1.4v 1.41 1.42 is healthy DDR4 is very low power even at higher voltages, so it doesn't get very hot. Extreme overclockers are routinely running Samsung B-die DDR4 at 1.9V-2V for benchmarking purposes on AIR cooling. The SOC isn't the most power consuming part of the CPU, so you should be safe going up to your Vcore, but you have to keep in mind that these parts were most likely not designed to handle too much power so be reasonable with the voltage.