Dell G16 7620 discrete GPU high power usage when not in OS or suspended

Hello!

I recently discovered that my laptop "turns on" its discrete GPU when suspended or working outside of OS. Unfortunately I cannot confirm ATM if this issue persisted from start or appeared only recently, after one of firmware updates.

Symptoms:
When suspended, main vent outtake behind keyboard becomes noticeably warmer. Both Windows 11 and Linux Mint 21, when resumed, report GPU temperature around 60-65 degrees, fans running noticeably louder until everything is cooled down.
Fans are also noticeably louder when I'm in UEFI setup, which may also indicate GPU activity.
Meanwhile, everything seems to work relatively smoothly when running inside OS, under either Windows or Linux driver.

Unfortunately UEFI doesn't provide option to turn DGPU completely, only to switch to it.

Any ideas what that may be, how to remedy it?

Thanks