I have had the same experience as SirLancelot with regards to upgrading iMacs.
I previously had a 2017 iMac running Catalina that was running Magic Arena fine. I recently upgraded to a 2020 iMac running Big Sur, and I frequently get crashes that locks up the entire computer forcing a complete reboot.
2020 iMac running Big Sur with MTGA crashes:
Model Name: iMac
Model Identifier: iMac20,2
Processor Name: 10-Core Intel Core i9
Processor Speed: 3.6 GHz
Number of Processors: 1
Total Number of Cores: 10
L2 Cache (per Core): 256 KB
L3 Cache: 20 MB
Hyper-Threading Technology: Enabled
Memory: 64 GB
System Firmware Version: 1554.80.3.0.0 (iBridge: 18.16.14346.0.0,0)
I have had the same experience as SirLancelot with regards to upgrading iMacs.
I previously had a 2017 iMac running Catalina that was running Magic Arena fine. I recently upgraded to a 2020 iMac running Big Sur, and I frequently get crashes that locks up the entire computer forcing a complete reboot.
2020 iMac running Big Sur with MTGA crashes:
Model Name: iMac
Model Identifier: iMac20,2
Processor Name: 10-Core Intel Core i9
Processor Speed: 3.6 GHz
Number of Processors: 1
Total Number of Cores: 10
L2 Cache (per Core): 256 KB
L3 Cache: 20 MB
Hyper-Threading Technology: Enabled
Memory: 64 GB
System Firmware Version: 1554.80.3.0.0 (iBridge: 18.16.14346.0.0,0)
Chipset Model: AMD Radeon Pro 5700 XT
Type: GPU
Bus: PCIe
PCIe Lane Width: x16
VRAM (Total): 16 GB
Vendor: AMD (0x1002)
Device ID: 0x7319
Revision ID: 0x0040
ROM Revision: 113-D1820Q-231
VBIOS Version: 113-D182A2XT-013
Option ROM Version: 113-D182A2XT-013
EFI Driver Version: 01.01.231
2017 iMac running Catalina with NO crashes:
iMac (Retina 5K, 27-inch 2017)
Processor: 4.2 GHz Quad-Core Intel Core i7
Memory: 64 GB
Graphics: AMD Radeon Pro 580 8 GB