ROG STRIX Z790-F GAMING WIFI II very slow Boot

[Volter_111222]

Hello,

Here are my PC specifications:

Motherboard: ROG-Strix Gaming-F WIFI-II D5
RAM: 128GB Corsair DDR5 (4 x 32GB, Vengeance RGB, 5600MHz)CMH64GX5M2B5600C40
Graphics Card: ASUS 4060 Ti
Power Supply: ASUS TUF 1000W Gold
SSD: SAMSUNG 980Pro 1TB
CPU: Core i9-13900K

It takes approximately 50 seconds to start when I turn on my PC. After pressing the power button, the PC begins to operate, but nothing displays on the monitor. After about 50 seconds, it beeps and then shows the BIOS screen. Occasionally, after pressing the power button, it takes about 30 seconds without any display on the monitor before it suddenly turns off and restarts. After another 10 seconds, the display appears.

Before buying this motherboard, I spoke with an online agent in the ASUS chat section, who assured me that all my components were compatible with each other. (We checked the SSD by removing it and adding it back to the motherboard to investigate the delay issue.)

I have enabled fast boot mode, set the POST delay time to zero, and updated my BIOS to version 1801. However, these changes have not resolved the issue. 

I would greatly appreciate your assistance in resolving this problem. Thank you.

[Silent_Scone]

Hi @Volter_111222 

Ensure Fast Boot is enabled. This should circumvent certain POST stability tests. The lengthy boot time could be attributed to the amount of memory in the system performing training routines to ensure stability. Boot > Boot Configuration. If unable to find the setting, use the UEFI search function.

[Volter_111222]

Dear Silent_Scone,

Thank you for your comment. As I mentioned, this option is enabled. In my point of view, 50 seconds for evaluating the 128GB RAM performance  is something weird. and,

"Occasionally, after pressing the power button, it takes about 30 seconds without any display on the monitor before it suddenly turns off and restarts. After another 10 seconds, the display appears."

what I have done:

1)Enabled fast boot mode

2)Set the POST delay time to zero

3)updated my BIOS to version 1801

4)Enabled XMP.

[Silent_Scone]

Could be retraining attempts causing the delay. You're combining memory kits, which is not recommended or supported by memory or motherboard vendors.

Remove one of the kits and retest POST times.

[Volter_111222]

 Thank you for your message. I have removed two RAM slots following the guidelines in the manual.

The same results persist.I consulted with the ASUS representative regarding my RAM model, and they confirmed that this motherboard is compatible with it.

I am using 4 x 32GB (CMH64GX5M2B5600C40) instead of the CMH128GX5M2B5600C40, which the ASUS agent assured me would be compatible. Unfortunately, since more than a month has passed, I am unable to return them to the seller.

I disabled XMP and set the default DRAM frequencies to 4800MHz and 4600MHz, but the issue remains unchanged. What frustrates me is that every time I power off my PC for about a minute and then turn it back on, this problem recurs:

"Occasionally, after pressing the power button, it takes about 30 seconds without any display on the monitor before it suddenly turns off and restarts. After another 10 seconds, the display appears."

[Silent_Scone]

Nobody should have told you that combining kits would be compatible, sorry. Memory kits are binned by memory vendors in the density in which they are sold. If you still have this correspondence, feel free to share it with me via PM.

Is the memory kit you've purchased on the QVL?

[Volter_111222]

I use two identical memory kits with the same timing and size (2*64).

In the QVL, it is mentioned that we can use(Image uploaded above)

CMH128GX5M2B5600C40: 128GB, which is not on the market.

But I use

CMH64GX5M2B5600C40: 2*64GB

As you can see, both are from the same company and have the same frequency and timing. I think the two memory is exactly the same, Am I right?

[Jiaszzz_ROG]

Hello @Volter_111222 

We recommend referring to the "Purchasing and Installation Guide" on the ROG STRIX Z790-F GAMING WIFI II QVL page:

Ensure that all memory modules are from the same validated memory kit. Do not mix DIMMs from different memory kits—even if they are the same brand and model (e.g., two DIMMs each from two different memory kits). Mixing and matching DIMMs can result in a failure to boot and compatibility issues. In particular, the stability of a system with mixed DIMMs cannot be guaranteed when XMP (Intel)/D.O.C.P (AMD)/EXPO (AMD)/AEMP/AEMPII is enabled. For example, enabling XMP (Intel)/D.O.C.P (AMD)/EXPO (AMD)/AEMP/AEMPII to speeds above DDR5 4800MHz or above DDR4 3200MHz could result in an unstable system.

As Silent_Scone has mentioned, please avoid mixing memory modules from different kits.

Thank you.

[Silent_Scone]

as above, it doesn’t matter what the other sticks are, or what kit they are from. Vendors bin kits in the density in which they are sold. Adding more memory invalidates the profile, and concessions may need to be made (manual tuning).  There’s only so much guidance one can give you in that situation.

Use a single kit validated on the MB QVL as per Jiaszz’s response.

[Volter_111222]

I appreciate your responses and thank you for your explanation.

Regarding the QVL, I can use four 48GB modules: either CMK192GX5M4B5200C38 (Version 3.53.02) or CMH192GX5M4B5200C38 (Version 5.53.13).

In my research, some users mentioned that CMK192GX5M4B5200C38 is more stable than CMH192GX5M4B5200C38. Is this correct? Here are the links for reference:

https://www.amazon.com/CORSAIR-VENGEANCE-5200MHz-Compatible-Computer/dp/B0BY6Y85PZ?th=1

https://www.amazon.com/CORSAIR-VENGEANCE-5200MHz-Compatible-Computer/dp/B0BY6ZF5KF?th=1