Continue from [GUIDE] Fixing HT for Coffee Lake CPUs on Skylake and Kaby Lake motherboards (Z170, Z270)
After 2 years of comparing, trying and disassembling, I finally got the key to access 16 threads on all these mainboards. Flashed BIOS over 200 times and looked into assembly codes over 200 modules.
The threads limit located in 2 modules, one is CpuMpPei, which mentioned by @s.napi already.
And the hex patterns only support original 8 threads. While some Z370 or 100/200s mainboards with new Intel RC code support 12 threads initially on this PEI module.
So here are the new hex patterns to replace:
You can only find one, though I give you three.
Lines are independent, one line for one hex pattern.
Search:
6B C0 0C 8D 8C 18 78 05 06 00
8D B8 00 00 06 00
00 B9 A0 02 00 00
Replace with:
C1 E0 04 8D 8C 18 58 06 08 00
8D B8 00 00 08 00
00 B9 80 03 00 00
Search:
6B C0 0C 8D 84 18 78 05 06 00
8D B8 00 00 06 00
00 B9 A0 02 00 00
Replace with:
C1 E0 04 8D 84 18 58 06 08 00
8D B8 00 00 08 00
00 B9 80 03 00 00
Search:
8D BE 78 05 06 00
8D B8 00 00 06 00
00 BE A0 02 00 00
Replace with:
8D BE 58 07 08 00
8D B8 00 00 08 00
00 BE 80 03 00 00
And for fully 16 threads unlock, you need search and replace these hex patterns in PlatformInitPreMem:
Replace C7403800004000 with C7403800008000
You will find these hex patterns in PlatformInit too, according to my test seems these code affect nothing, so if you like, you can replace it in PlatformInit too, or you can leave it as original.
In CpuPei you will find C7402700004000, you can replace it with C7402700008000, or leave it as original, it doesn’t matter too.
For MSI 100s mainboards with 16MB full Click BIOS UI, it can not boot with 6 cores CPU initially.
After replace every modules I got the key.
Search 81 79 20 00 00 64 00 in MFlashPei and replace with 81 79 20 00 00 3B 00, the value supposed to be the size of DXE volume but I can’t understand why it will reject 6 cores boot but 8 cores boot normally.
And 00 3B 00 00 is copied from MSI 100s 8M BIOS mainboards, which do not have this BUG.
According to my test, I can’t see the side effect of this modification, though I still don’t know why to edit this, it just works.
I got the 16 threads fix in Augest 2020, the MSI 100s fix in November 2020. Because some people keep annoying me for modifying their BIOS with rude request, selling my modification and defaming me.
I even want to keep it secret forever. But, it’s not cool to punish all people by keep hiding that.
So, enjoy it!
dsanke god forever!
Thanks for your hard working and generous sharing!
dsanke god forever!
Thanks for your hard working and generous sharing!
D大66666! D神无敌! D神威武!
Well done! Now, finally, everyone will be able to prepare a bios with 16t support. Thank you for sharing this with us. Respect.
Awesome work, thanks for sharing!
I see Svarmod has also released CoffeeTime 0.99 
Hi dsanke
Soooo sorry to disturb you here.
I would claim that my reason of keeping it in use is that 770DMG is the latest module which support standard-MXM Quadro Graphic and 9th Intel will support ideal performance and less heat. The official BIOS also support Linux. However, seems that you do not wanna help me by offering the perfect BIOS of 770DMG directly may because it is more or less like a deal. For this decision, I can fully understand and take respect.
Recently I had a rough view of relevant knowledge in the SMXDIY. Method V4.3 Beta is friendly and simple that I can carry on with by myself. Since it looks reasonable, may I simply apply it on my BIOS?
If not, which additional steps should be used?
Should I use your patterns here?
@meokyo
You can do whatever you wanna do on your device. But if you’ve read my threads, you should know that thread is totally useless for you.
Congratulations for finding the code. It is so satisfying once you reach your goal in reversing job. I surely can understand/appreciate the effort it takes to do such challenging task 
I guess I would use 6 core cpu…
Congratulations for the code!
dsanke 被遗忘的1151又再次被你点燃
Your mod is working on my ASUS G20CI (H270) with i9 9900k (R0). It is now running on 8C/16T.
Congratulations!
Hi! What BIOS are you using? I’m trying to get my 9700K to work with g20ci mobo.
Hey @s.napi , I was see about your method. I don’t know how to fix this in bios. can you suggest me something how can i began study about this backwards？Thank you.
well, you can upload your bios here, and tell us which cpu you would like to use when you modified your bios.