Here is three different things that solved video problems in all our Win7 and Win10 laptops:
When using original power supply that supply laptop (but not charge at the same time) there is something probably in BIOS that slow down graphic card to save energy. That makes processor do some of the graphics calculations. (And actually consume even more energy!)
Solution: Go on battery or use a large powersupply (in our case 120W)
How to quick check if this is the problem: pull out powersupply, if this is the case, latency disappear in two seconds.
Nvidia powerful graphic cards use an engine called PhysX for games etc. It seams QGC does not use that.
Also QGC works default on motherboard graphic card, not on the more powerful Nvidia extension card.
Solution: In Nvidias “control panel” select under “Programs” QGC so Nvidia forces QGC to use Nvidia card.
Some graphic cards also needs tweeking in Nvidia 3D setup (same place as above line)
Real crazy in a few computers: Switch system fonts from 125% size to 100%
(Right click desktop, “adjust screen” then “monitor” translated from Swedish OS)
Check the 100% tickbox instead of 125%
Log out and log in again, fixed….