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Update Directly to macOS Big Sur

Lenovo M900 Tiny Big Sur

Successful upgrade:
- Catalina 10.15.7 installed with OpenCore 0.6.7
to BigSur 11.2.3 directly from App store

Lenovo M900 Tiny
CPU: Core i5-6600T
Intel HD Graphics 530
RAM: 8 GB
HDD: WD Blue 256gb SN550 NVMe + SSD Crucial BX500 1 TB
only Ethernet (no WiFi)
 

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Another late-to-the-party success story for the 2015 Mac in my profile. I first read up a lot on OpenCore. I watched some videos on copying items from Clover to OC, but in the end I decided to just follow the install guide here: https://dortania.github.io/OpenCore-Install-Guide/.

I used a USB drive until I had a working boot, and then I copied my Clover EFI to a safe location, deleted the Clover EFI on my main HD, and replaced it with the USB OC EFI I just created. On this MB, I had to use alcid=2 to get sound under Catalina.

After downloading and running the Big Sur install from the App Store, I had a working Big Sur boot but no sound. Changing alcid back to 1 got me sound over HDMI again.

Overall it was about 2 hours of reading through OC setup and watching Youtube videos, a solid hour actually setting up OC and getting it to work on Catalina, then about 30 minutes to install Big Sur.
 
* Create OC EFI folder (Kexts, ACPI, config.plist, etc) using Kaby Lake Guide
* Delete Clover EFI on my Catalina installer USB, replace with new OC EFI folder
* Boot from Catalina installer USB, and select my Catalina OS Hard drive as boot device, verify everything is working as expected (Audio, Messages, Airplay, Bluetooth, wireless, etc)
*Delete Clover EFI from internal EFI partition, replace with working OC EFI folder from Catalina USB install disk
*Reboot, cross fingers, verify that computer boots properly with new OC EFI folder
*Verify all the things
Thanks very much for this - it's the most concise description I've read so far of how to migrate from clover to opencore. (Haswell system and OC 0.6.8 but otherwise identical- although I did my backup first in the above procedure so took that line out). For some reason mentally I had a bit of a fear that messing with OC would break things, but your approach was cautious.

I actually did slightly different (updated to catalina first in clover and then did the OC switch), but I doubt that matters; also the Catalina installer was not the most recent so I let it run through the subsequent security updates, also with no issues. (I do intend to update to Big Sur in a bit but I like to give it a few weeks to shake out any oddities or bugs)

One note: I followed the instructions about removing S/L/E kexts ie. moving to the new paradigm of having all kexts on the hackintosh side on the EFI partition - and I did this before the OC switch.

So in case of use to anyone (again, not saying best, but worked):
-Careful backup.
-Catalina update: updated clover first using multibeast/tonymac recommendations. Rebooted to check.
-Otherwise standard system update using install catalina from app store. (A bit out of date).
-Removed kexts from s/l/e per tonymac recommendations. Rebuilt kext cache. Again, a few unrelated reboots to check and a day or two (just to shake out issues).
-Built EFI folder and config.plist for OC. Installed on USB/install catalina drive.
-Boot from USB / OC, select Catalina drive as MacOS system boot.
-After checks, copy EFI folder from USB/catalina install to MacOS system boot.
-After checks, install system updates (no different from Mac hardware).

Side note: copying System UUID, hardware serial, etc., from the existing clover boot (slightly different iMac model) to the OpenCore config.plist worked fine. iCloud logins etc had to be confirmed but as usual.
 
Please post your question(s) as a standalone thread in the Big Sur Desktop Support forum section. Violators will have their post removed.
 
Great update 11.7.10.. now Unigine heaven runs much more fps around 130.
 
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