ASUS X99 Boards - Big Sur (Not Compatible)

[chibibowa]

Me and numerous other people have tried to get Big Sur working on ASUS X99 Boards. MSR (CFG Lock) Patched or not, doesn't matter. RTC Patch or not, doesn't matter.

You will most likely get a CR2 Error, I have seen many threads discussing this error and nobody seems to be able to provide a solution to it. I asked on discord about it and after having tried many possibilities, here is his conclusion:

This is the error I get (and many others too):

Until proven otherwise, you can forget about getting Big Sur working on any (ASUS?) X99 Boards. Period.
EFI (OpenCore 0.6.0) attached. If you want to wander around, maybe you can find something that I missed, though; I have little hopes for a magical solution...

 

[Kingofelephants]

Me and numerous other people have tried to get Big Sur working on ASUS X99 Boards. MSR (CFG Lock) Patched or not, doesn't matter. RTC Patch or not, doesn't matter.

You will most likely get a CR2 Error, I have seen many threads discussing this error and nobody seems to be able to provide a solution to it. I asked on discord about it and after having tried many possibilities, here is his conclusion:

View attachment 486883

View attachment 486884

This is the error I get (and many others too):

View attachment 486885

Until proven otherwise, you can forget about getting Big Sur working on any (ASUS?) X99 Boards. Period.
EFI (OpenCore 0.6.0) attached. If you want to wander around, maybe you can find something that I missed, though; I have little hopes for a magical solution...

We need KGP to come out from retirement lol

 

[ITzTravelInTime]

That was me, and also i took this info from the open core desktop guide in the section about big sur, i have also to point out that people with some cinese x99 motherboards were able to boot, since this issue comes from a faulty implementation in the bios-side made by mobo oems, perhaps intel put this restricted rtc implementation as part of their reference firmware and cinese manifacturers took a different route implementing the bios

 

[ITzTravelInTime]

here is an update (you can see as an attachment inside the spoiler) from vit9696 who is one of the main devs of open core, he basically says that this is an issue with the way mobos handle something related to pci devices basically and how the os expects them to be handled instead. The poper way to find a solution is to have a the source code release for iopcifamily.kext and do some work to debug the problem to then create a bootloader patch or some other solution, the open core team will also not work on that at least in the near future (probably because supporting big sur still requires lots of work still to be done, and also because not having a source code release and so using reverse engennering tools requires to waste lots of time figuring out what the code does)

Spoiler: Spoiler

 

[esafeddie]

here is an update (you can see as an attachment inside the spoiler) from vit9696 who is one of the main devs of open core, he basically says that this is an issue with the way mobos handle something related to pci devices basically and how the os expects them to be handled instead. The poper way to find a solution is to have a the source code release for iopcifamily.kext and do some work to debug the problem to then create a bootloader patch or some other solution, the open core team will also not work on that at least in the near future (probably because supporting big sur still requires lots of work still to be done, and also because not having a source code release and so using reverse engennering tools requires to waste lots of time figuring out what the code does)

Spoiler: Spoiler

View attachment 487253

In another post, he also mused that Clover Devs should give up on Clover and maybe come over to the OC side and collaborate with further development of OC, as the concept and operation is more compatible with real Macs as well as hacks, whereas Clover is more a brute force operation boot loader. Maybe not his exact words but the gist of his thinking.

 

[ITzTravelInTime]

with some time i have also tested all the ssdt patches and none of them worked, meybe i am getting something wrong or i need to tweak some values but it didn't worked for me. now i am curious to see the ssdt of one of those cinese x99 motherboards which actually boots into big sur to see what's different compared to my system

 

[Kingofelephants]

That was me, and also i took this info from the open core desktop guide in the section about big sur, i have also to point out that people with some cinese x99 motherboards were able to boot, since this issue comes from a faulty implementation in the bios-side made by mobo oems, perhaps intel put this restricted rtc implementation as part of their reference firmware and cinese manifacturers took a different route implementing the bios

do you know what model of that board?

 

[nyu1985]

huananzhi x99-f8 for example.

 

[ITzTravelInTime]

any owners of chinese x99 motherboards willing to send me their dsdt and ssdt?

 

[ITzTravelInTime]

We (on another forum i don't think i can mention here) are making some experiments trying to get the system to boot via dsdts, we recieved some dsdts from a guy who managed to get big sur to work on a chinese x99 board and we are looking for possible stuff to attempt at a patch