Installer boot: CSM support enabled getting black screen/CSM disabled results in garbled graphics

[ghost]

Hi, thanks for sharing your efforts here. I followed your recipe thoroughly assuming making macOS installer inside the Virtual Box macOS VM.
Unfortunately lack of success with booting the installer:

1. Enabled CSM support in BIOS - this results in hanging completely with black screen (lights on) right after choosing to boot from the USB installer stick
2. Disabled CSM support in BIOS (mentioned here: https://github.com/jsassu20/Lenovo-T450-Catalina-OpenCore) - this gives me console mode boot but then when entering graphics the screen is totally garbled.

Any suggestions would be much appreciated.

Platform:
System Manufacturer LENOVO
System Model 20BWA04FPB
System Type x64-based PC
System SKU LENOVO_MT_20BW_BU_Think_FM_ThinkPad T450s
Processor Intel(R) Core(TM) i7-5600U CPU @ 2.60GHz, 2594 Mhz, 2 Core(s), 4 Logical Processor(s)
BIOS Version/Date LENOVO JBET73WW (1.37 ), 14/08/2019
SMBIOS Version 2.7
Embedded Controller Version 1.04
BIOS Mode UEFI
BaseBoard Manufacturer LENOVO
BaseBoard Product 20BWA04FPB
BaseBoard Version SDK0E50510 WIN
Installed Physical Memory (RAM) 12.0 GB
Total Physical Memory 11.9 GB
Name Intel(R) HD Graphics 5500
Adapter Type Intel(R) HD Graphics Family, Intel Corporation compatible

[racka98]

Follow the guide i linked in my post. CSM support should be enabled. Preferably you should reset bios to default settings and change the settings as recommend.

You are probably getting a black screen because the installer is not correctly made.

Recheck your usb drive

Did you pass through your USB drive in VM?

Also is it a thumb drive or an external hard disk/drive?

[ghost]

Hi, Thanks for the feedback. I gave it one more chance and must again confirm that with CSM Enabled the installer doesn't start at all.
However, with CSM Disabled and connected to an external monitor (and boot screen in BIOS set to VGA) I was able to get proper graphics on my laptop LCD screen - totally weird!

I was able to install Big Sur 11.1 successfully. However I found other issues which I would put into other issues here.

[ghost]

Another ridiculous tip: close and reopen laptop lid. No need to connect to external monitor.