@KedarWolf - thanks, but nothing needed to be lost this time around, all original microcodes remain + 906EC
Good luck and hope it works for you, this method of what you are trying I mean, BIOS/mod will be fine as it is! Flash using USB Flashback
Thank you!!
I’m at work right now, but will try soon as I get home.
I’m so grateful, on my 8700k, 1101 with updated microcode etc. was so much more stable than the latest, 1704. 
@panosxidis - same/same, that is microcode version ID, so you already have latest installed.
@KedarWolf You’re welcome! Hopefully it works for you that way - Fingers crossed!
i have one question latest microcode is always stable and more perfomance?or not?thank you very much!
No, not always, it’s only considered best for security and up to date with most fixes. Other older may be better for stability/performance, but can be less secure to possible hacks like Meltdown/Spectre recently.
BIOS doesn’t work. Black screen on boot, Q-Code 18. I even tried updating the SATA/RAID, GOP and Ethernet firmware first, no luck. 
Edit: UBU Tool says the microcode is installed, can even update all the microcodes in UBU Tool, no luck there either. 
Maybe your edits cause the failure? Did you test without any of that, as I sent it? If not your edits, I assumed it might not work that easily, due to all the things I tried to explain to you.
To confirm what I mentioned is correct, try it with the other older CPU, if it works then it’s as I mentioned.
UBU microcode updating? I showed you in image it was updated as requested, but much more than that will be needed for what you want to do.
I did try it without editing it all all, just downloaded the original you sent me, no go. I no longer have the 8700k but a 1101 BIOS works with an 8700k with or without updating the microcode in UBU Tool.
Thanks for your help still, I think because the BIOS originally doesn’t support that microcode it’s causing issues like you said.
You’re welcome. I think many other modules would need updated for that to work, starting with the ones I mentioned originally but that may not be all required
I think it’s a problem with the microcode as I tried updating the RAID/SATA modules, the GOP modules and even the Ethernet modules on your modded BIOS, black screen on boot. I get the same error code with the 1101 BIOS without the microcode update and the 1704 BIOS works fine with all those updated exactly the same way. I’m pretty sure the 906EC is the 9900k microcode but I’m not 100% sure of that. It might be that I suggested the wrong microcode for you to update but I can only find vague references to the microcode a 9900k needs.
Edit: As you know I also tried without updating any of the other modules on your modded BIOS.
It could be, sometimes only a certain microcode version works, but that’s usually when trying one “Gen” cpu older or newer and is more rare.
GOP AND vBIOS would be ones that would need edited/updated, as well as setup module, and possibly AMITSE/AMITSE Setupdata, also possibly ACPI Table, CPUInit modules, Powermanagement modules, and PCIE patches and ME SKU change may also need applied as well
Sorry for not checking before and only taking your mention of that microcode, but I checked now and you are correct and CPUID is 906EC
http://www.cpu-world.com/CPUs/Core_i9/In…20i9-9900K.html
8700k is i7, 9900k is i9.
Edit: If I update the 1704 BIOS with that latest 906EC microcode I mentioned to use it works fine so I’m not sure what’s going on other than there has to be some compatibility issues with the microcode and adding it to the older BIOS.
I know, you wanted 9900K added 906EC, that’s what we did. Yes, I told you from the beginning adding microcode alone may not be all that’s needed, many other modules as mentioned will need edited/updated or swapped in from the other BIOS.
Yes, I know, I wasn’t trying to be sarcastic. Was in relation to "It could be, sometimes only a certain microcode version works, but that’s usually when trying one "Gen" cpu older or newer and is more rare. "
I think your only ideal option may be to use latest BIOS and get used to it, once you play a while you’ll get your CPU stable how you like again too. Old BIOS, even with new microcode added, and then all the mods required, once if ever working would no longer be that stable BIOS you like anyway since it would be heavily edited.
And that’s stability you desire may only be due to that CPU, you used long enough to find it’s sweet spot with that BIOS, same needs done with new CPU and updated BIOS is all.
Anyone know if a bios has Bootgaurd will it be possible to mod the microcodes? This is for a Gigabyte Z390 Master board.
Thanks
@CodeRush ,
Do you think using "FPTW64 -f " to flash a modded rom file on a system that has bootguard in place would work?
I have a Gigabyte Z390 Master motherboard that will not accept my modded bios files within its qflash application.
Can you please advise?
Thank you
Depends if bootguard is setup properly or not, which it’s probably not 
Run MEInfowin and post the bottom of the results, or just check if you see Measured boot and verified boot on the left FPF side enabled, if they are both enabled at FPF side, then send me a BIOS dump and I can see if the rest is configured properly thus enabling bootguard fully
If measured boot and verified boot are not enabled on the FPF side, then no, bootguard is not active
I replied to your PM about the Qflash issue, and posted in another thread too. That can easily be solved
Here are those results you requested. Looks like its disabled. So modding the microcodes should be doable once the QFlash security has been disabled.
Not in a rush to do it at this moment however…
Thanks
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--- --- -----
Key Manifest ID Not set 0x01 0x01
PTT Not set Enabled Enabled
SPI Boot Source Not set Enabled Enabled
Enforcement Policy Not set 0x00 0x00
OEM ID Not set 0x00 0x00
TXT Supported Disabled Disabled Disabled
OEM Key Manifest Present Not Present Present Present
OEM Platform ID Not set 0x00 0x00
SOC Config Lock Not set Not Done Not Done
Persistent PRTC Backup Power Enabled Enabled Enabled
EK Revoke State Not Revoked Not Revoked Not Revoked
CPU Debugging Not set Enabled Enabled
BSP Initialization Not set Enabled Enabled
Measured Boot Not set Disabled Disabled
Verified Boot Not set Disabled Disabled
Protect BIOS Environment Not set Disabled Disabled