B650 + Corsair Vengeance DDR5-6400 64GB: boot loop

nixtosay wrote: Hi I have just finished a new PC build using the B650 PG Lightning Mainboard with Corsair's DDR5 64 GB Vengenance (CMK64GX5M2B6400C32). When booting into the BIOS the memory banks are being detected in the A2/B2 slots with their total memory correctly. However, the frequency is stated as 4800 MHz. I was expecting the memory to run at 6400 MHz. So I adjusted the speed accordingly, loaded the detected XMP profile in the submenu, save all changes that come with it and reboot. However, the pc then reboots automatically and I am not able to get back to the BIOS. After a complete power off I can get back to BIOS where the memory again is stated @ 4800 MHz. Am I doing something wrong? What do I need to do in order to run the advertised 6400 MHz? I noticed a lot of different parameters have changed when I loaded the XMP profile - do I need to find these values by myself and adjust? I am by any means not experienced in overclocking and don't intend to. Any help is appreciated.

update to newest bios,

the first memory training takes up to 5 minutes (after the training it boots fast)

you reboot the PC before the training ends or the training fails - the motherboard resets the RAM settings to stock 4800mhz,

so i would wait that 5 minutes, if it fails training try changing the training options to 'auto' like described here:

https://forum.asrock.com/forum_posts.asp?TID=30954&title=solved-b650m-hdv-m2-bios-memory-stability-issues

it says DDR5-4800-*capacity* @ *current speed*

if its boot looping proceed like i described in my previous post

nixtosay wrote: I have just applied the settings as advised. Works like a charm. It is reading just as you are describing: DDR5-4800-32GB @6400MHz Thank you M440

thank you for letting us know,

As this system has just been setup and everything is out of the box, is there something that you would recommend taking a closer look at? Or certain settings that I should apply? I greatly appreciate your help.

Nothing if you plan to run the setup at stock.

If you like tuning you can undervolt the CPU (PBO2 Curve Optimizer).

nixtosay wrote: Hi M440, I kind of need to revert what I have said previously. As described earlier, I was able to set the memory clock speed to 6400 MHz. As I am running Debian Sid 6.7.9-amd64 with an NVidia 4070 Super using driver version 550.54.14 the system became very unstable. I noticed first by not being able to start any games using Steam. In addition, I booted into memtest86+ and was confronted with failures half way through the test. Tried stepping down with the frequency still following your guide until I was able to run the system stable at 5800 MHz. Will this be improved with upcoming BIOS updates? Can I report this to ASRock directly to have a look into this? Or are you part of ASRock's team?

have you applied the xmp/expo profile?

i use arch btw

biosbandit wrote: I am about to purchase exactly the same memory, 2x32GB sticks for a B650i (ITX) AsRock system. Which CPU are you using? Have you had any luck in isolating this issue? Often memory issues are easily fixed with simply a tiny bit more voltage. These seem to be 1.1V modules, it may be worth going to 1.15 volts for example. However, this is old information from long ago, I am unsure if it's still valid.

Hi biosbandit,

The state as of now is that I was able to have a stable system going @ 5800 MHz as of now.

Please keep in mind that I have absolutely no clue about voltages and the different settings I could apply in that regard. So chances are that running them at the suggested clock speed of 6400 MHz is possible. I just have not figured it out - yet.

In Debian Sid a dmidecode provides me with this information:

Handle 0x0015, DMI type 17, 92 bytes
Memory Device
     Array Handle: 0x0010
     Error Information Handle: 0x0014
     Total Width: 64 bits
     Data Width: 64 bits
     Size: 32 GB
     Form Factor: DIMM
     Set: None
     Locator: DIMM 1
     Bank Locator: P0 CHANNEL A
     Type: DDR5
     Type Detail: Synchronous Unbuffered (Unregistered)
     Speed: 4800 MT/s
     Manufacturer: Unknown
     Serial Number: 00000000
     Asset Tag: Not Specified
     Part Number: CMK64GX5M2B6400C32
     Rank: 2
     Configured Memory Speed: 5800 MT/s
     Minimum Voltage: 1.1 V
     Maximum Voltage: 1.1 V
     Configured Voltage: 1.1 V
     Memory Technology: DRAM
     Memory Operating Mode Capability: Volatile memory
     Firmware Version: Unknown
     Module Manufacturer ID: Bank 3, Hex 0x9E
     Module Product ID: Unknown
     Memory Subsystem Controller Manufacturer ID: Unknown
     Memory Subsystem Controller Product ID: Unknown
     Non-Volatile Size: None
     Volatile Size: 32 GB
     Cache Size: None
     Logical Size: None

Handle 0x001A, DMI type 17, 92 bytes
Memory Device
     Array Handle: 0x0010
     Error Information Handle: 0x0019
     Total Width: 64 bits
     Data Width: 64 bits
     Size: 32 GB
     Form Factor: DIMM
     Set: None
     Locator: DIMM 1
     Bank Locator: P0 CHANNEL B
     Type: DDR5
     Type Detail: Synchronous Unbuffered (Unregistered)
     Speed: 4800 MT/s
     Manufacturer: Unknown
     Serial Number: 00000000
     Asset Tag: Not Specified
     Part Number: CMK64GX5M2B6400C32
     Rank: 2
     Configured Memory Speed: 5800 MT/s
     Minimum Voltage: 1.1 V
     Maximum Voltage: 1.1 V
     Configured Voltage: 1.1 V
     Memory Technology: DRAM
     Memory Operating Mode Capability: Volatile memory
     Firmware Version: Unknown
     Module Manufacturer ID: Bank 3, Hex 0x9E
     Module Product ID: Unknown
     Memory Subsystem Controller Manufacturer ID: Unknown
     Memory Subsystem Controller Product ID: Unknown
     Non-Volatile Size: None
     Volatile Size: 32 GB
     Cache Size: None
     Logical Size: None


I would love to learn more about what could be done to improve stability while going further towards the 6400 MHz.