I suspect this issue may have started with 1709 since GPU monitoring was added back then, but don't know for sure because I skipped that version on this laptop.
So the system is a Lenovo Z50-75 laptop ( FX7500 APU with R7 graphics and M260DX dedicated card) which should work without issues with Windows 10.
The problem is every time I launch the task manager it wakes up the dedicated R7 M260DX card and it won't go back to "sleep" even if I close the task manager. This will cause the laptop to produce more heat and increase the fan speed. I used HWiNFO to detect this (I disabled waking up GPU's in HWiNFO of course).
So far I've tried several drivers: the Windows 10 default, 16.300.2201.0 from the Lenovo site, 18.5.1 from the AMD site (latest driver that actually supports 1803) all of them has the same issue, even if I force the Integrated card for taskmgr.exe it still wakes up the GPU and the only way to disable it is disabling then enabling it again through the device manager and the driver will put it back to sleep.