I tried a test with my Monitors and it seems to have somehow corrected the problem.
Here's my setup:
I have three monitors:
- Left Monitor (1) Connected to NVIDIA card
- Centre Monitor (2) Connected to Intel Integrated Display (in CPU)
- Right Monitor (3) Connected to Intel Integrated Display (in CPU)
For the Test I disabled the Centre and Right Displays, then started Fusion 360 and it opened correctly on the Left Monitor (using NVIDIA card).
While Fusion 360 was still open, I enabled the Centre and Right Monitors.
I could then move the Fusion 360 Window to either of the Centre or Right Monitors and it still worked correctly.
It looks like something was messed up with the Intel Graphics Drivers (or the Fusion 360 connection to Intel Graphics Drivers).
Now everything seems to be working fine including opening Fusion 360 from either the Centre or Right Intel Displays.
If I start Fusion 360 from the Left Display (NVIDIA Card) it looks like it is always using the NVIDIA GPU even when I move the Fusion 360 Window to either of the Intel Displays (Centre or Right Monitor).
Hopefully this bit of information might help others that are having similar issues.
Thanks