I think I figured it out, I managed to disable CSM by default and enable 4g decoding on default through AMIBCP 4.55 for an X79 motherboard - which should be a similar idea to Z87.
The reason why it doesn’t work sometimes is because simply there are more than one instance of the setting enabled or disabled, so all of them need to be set to default and failsafe for it to work - Usermode for all menus and submenus that contain it seems to help it show up, too.
so in your Z87 there is no string for above 4g and csm toggle, but could you manage how to find/enable the above 4G and force it to CSM Off if there is no such option through amibcp?
Please read above, X79 is the motherboard that I managed to verify it on, an Asrock X79 Extreme 6 Motherboard
Also got it working for all of 1 reboot on windows 11 with a 9980HK on a Maximus VIII Hero. I remember reading about deleting a DXE to make space for the driver – or perhaps put it at the front of the DXE stack?
I’m working on the Z87 bios tonight
Interesting, I can find “Above 4G Decoding” string to token ‘0x0F97’ in the bios file with AMIBCP v4.53.
But it is unable to find this string in the “Setup Configuation”, it’s even not a hidden option.
this is ASUS B85-Plus 2305 bios inserted with “NvmExpressDxe_5.ffs” and “ReBarDxe.ffs”, but when i’m trying to patch the DSDT follow the wikis, it is totally different, there is no CreateQWordField in my “DSDT.dsl”, is there anybody interested in it or you can help with it? thanks 
B85PLUSNVME_Bar.rar (6.5 MB)
Check everywhere, but Asus probably never even inserted it into the bios in the first place 
Got this now, the bios with the DXE installed and the CSM modes disabled? I think I pretty much covered all CSM mode settings.
https://drive.google.com/drive/folders/1qlKZ_LwmIetdKAjuCCY9eL3hB1QvtiSI?usp=share_link
Keep us updated, and thanks for helping hack it in 
One more thing, is there any way to inject TPM 2.0 compatibility instead of 1.2 only? I have some files dug out from an X99 Bios from Gigabyte’s SLI motherboard, which has TPM 2 code, but not sure if you can just drag and drop the corresponding 4 or so files – or if there’s anything else needed
@Wingklip I’m also interested in the TPM 2.0 mod so I can upgrade to Windows 11 and be able to play Valorant (requires TPM 2.0 on 11).
I wrote some of my findings here [Discussion] TPM 2.0 on unsupported motherboards
It requires DSDT modification in addition to DXE (especially the TPM SMI handler) and maybe PEI modules swap/add
Hello! I also have an Asus P8Z77V-Pro, stumbled upon this topic and got interested in trying to enable ReBar for my Powercolor Red Dragon RX570 4GB. Did not get around flashing just yet… For good measure i tried to disable CSM first and see if everything boots correctly. Problem is, after disabling CSM, the following message appears:
“The current BIOS setting do not fully support the boot device. Click OK to enter bios setup”.
So i’m kinda lost here. Is there something i could do to ensure windows boots with CSM disabled?
I´m using a Samsung Evo 500GB SSD as system installation (Plus another 1TB hard drive as storage and another USB3 external).
@Ed_Strider
So if you never booted your RX570 on an UEFI environment, that’s the culprit.
This means you system was by default using CSM Auto or ON and a legacy/mbr OS.
Its need UEFI/GPT
[Release] Resizable BAR BIOS EFI Module - BIOS/UEFI Modding / BIOS modules (PCI ROM, EFI and others) - Win-Raid Forum (level1techs.com)
Yup… I checked and found out i’m currently using MBR (Sorry!). Can i go for this procedure before attempting to disable CSM?
Sure… is it or are asking me that you wont have no issues with it and the operation will be 100% safe and risk free, no i wont be the one assuring you that.
That’s why the same article enfases it “The best approach is switching to UEFI and performing a clean install of Windows 11…”
Of course, there’s plenty user reports of successful conversions out there… don’t want to scare you.
Goo luck.
Will be the first thing tomorrow morning, thanks. In my previous installations, i had UEFI operating. But due to black screens and loss of video signal randomly (A nightmare, the only driver that seens stable is 20.10.1), i had to reset bios setting and install fresh windows 10 LTSC a lot of times, so not sure why it’s on MBR again (guess i went on with defaults without noticing).
A standard x64 ISO (or the way the boot source is prepared) will boot/install according the bios settings, UEFI (CSM Disable) or Legacy (CSM Auto/Enable) mainly, other combinations possible, ex. an UEFI system, later can boot in Legacy but never the other way around.
Hello again!
I sucessfully (kinda) converted my disk from MBR to GPT, and managed to turn off CSM.
But two things are happening and i don’t know if those will bite me in the arse afterwards.
1 - “MBR2GPT: Failed to update ReAgent.xml, please try to manually disable and enable WinRe” - So i just entered BIOS after disk conversion, disabled CSM and enabled UEFI instead… So system boots and no signs of any problems… Should i be worried?
2 - I have latest bios released by Asus for this board, 2104. I’m sure i disabled CSM, but GPU-Z is telling me otherwise… Should i be worried?
Google is your “friend”…
Well… these are those “tiny” details… it could be app scope or …
“damm… they were right, i should have made a clean new OS installation”
Conversion/cloning should always be the last resource, that’s why…anyway you’ll have to wait and see if no more issues appear in future, if it does…you know what to do.
Got it, sorry to post redundant questions, I was in a hurry and should made the basic research before posting. but in theory, all I have to do now is flash:
Z77VPREBAR.rar (3.9 MB)
And just choose to use amernime drivers or enable ReBar through reg key?
xCuri0/ReBarUEFI: Resizable BAR for (almost) any UEFI system (github.com)
EDIT: Sorry ReBAR not my strongest field… i just pointed the best thread for it.
Im not aware of that file mods right now, Asus doesn’t have revisions with different bioses.
Your call only but the bios version is valid as long is the same mb model.
I linked the flash guide cause the recommend method for your mb is USB BFB.
It needs a CAP file and, the ROM mod provided is not CAPSULE, you can exchange with an HEX editor on the original ASUS CAP file after 0x800 and rename it to Z77VO.CAP
Allright, i took a long reading on those links you provided, and i appreciate that you’re trying to guide me through the whole concept. But is it really necessary? Since my board is essencially the same as user Romulus_ut3 (Asus P8Z77-V-Pro), and he even provided a rom file:
https://winraid.level1techs.com/uploads/short-url/1GcLNu0HKkHnFNdh2oWvsr6iaPs.rar
Why should i not flash that rom file? As i understood, his modifications were made over a 2104 version (same as i´m currently using, last official bios rom provided by Asus for this board).
I know there would be different REV versions of many boards, but not this one i guess… So we can disregard that. Do i REALLY need to make all steps again?
Thank you so far for your patience.
