Comment # 95 on bug 76490 from Tobias Droste

$ cat /sys/kernel/debug/dri/0/radeon_pm_info

If you have debugfs mounted on /sys/kernel/debug

Are you suggesting that Microsoft Windows 10 is delivering a different VBIOS
for your card then what was originally installed on the graphics card?

If so, who installs this? Windows itself? As far as I know is the driver only
loading some binaries inside the VBIOS, but not replacing it. Or is this a new
feature of the windows driver?