I have written a shell script to check which soc node is broken on rk3582 soc.
You have to flash an armbian 5.10 legacy image of rock5c because it has modified uboot to unblock all good ip cores. If you flash 6.1 vendor image, you will get gpu enabled even you have broken gpu.
How to use:
curl --silent https://cdn.haguro.top/check-rk3582.sh |bash -
Result is in Chinese, you can use google translate for your language.