idk what to tell you man... I gave same board and cpu just different memory and gpu.. and my system is 100% stable.

For others following this issue;

I was never able to get my 13900KS to work properly regardless of the BIOS settings tried, including capping the power to 320 as well as 253, enabling C-States and all of the TVB settings. Eventually my system would randomly crash. I also think that this is definitely an issue where the CPU can degrade because it eventually started to crash even when sitting at idle.

I've taken the system down and installed a new 14900K, set the power cap to 253, and will wait to see if a new CPU addresses this issue for me. This 13900KS will go back to Intel for warranty replacement as well. If you've tried any of the available BIOS options and you still have system instability, it's probably time to send the CPU for warranty replacement, and/or get another one.
 
It would really be nice is EVGA could released one more BIOS update which includes the updated Intel recommendations/microcode for specifically addressing this issue.

Good Luck..

Your 13900KS was already cooked probably. Good that you RMAed it.

To close out this issue. It was finally addressed by updating the BIOS to the latest beta 1.17 version. Since updating, I haven't had a single issue with my system with the 14900K.
 
https://forums.evga.com/BETA-BIOS-for-Z790-0x129-Microcode-Update-m3625595.aspx
 
Good Luck..

jasnxl
To close out this issue. It was finally addressed by updating the BIOS to the latest beta 1.17 version. Since updating, I haven't had a single issue with my system with the 14900K.
 
https://forums.evga.com/BETA-BIOS-for-Z790-0x129-Microcode-Update-m3625595.aspx
 
Good Luck..

Thanks for the update, good to see your system is now stable

Yes, thank you for the update and glad to hear this is resolved.