Precision 7740 - Poor Gaming Performance

I apologise if this is not the place to post this, but I wonder if someone could shed some light on a problem I have whilst trying to run games, specifically Microsoft Flight Simulator 2020, on my Precision 7740, spec's below:

i9-9980HK (8 core, 16MB Cache, 2.4GHz up to 5.00 GHz Turbo, 45W)

64GB, 2x32GB DDR4 2666MHz Non-ECC Memory

Nvidia Quadro RTX 3000 w/6GB GDDR6

PCIe NVMe Class 50 SSD's

I have seen this game run pretty smoothly on lower spec'd machines so I was expecting it to be silky smooth on mine, however with no other programs running, windows and bitdefender set to games mode and ensuring that MFS2020 is using the dedicated GPU, even with all setting to minimum quality the game is unplayable, screen jerky, constant random popping noises from the speakers.

Looking at Performance under Task Manager I can see that the GPU is fluctuating wildly.

Erratic Game Play

However, after approximately 20 minutes of this jerky game play, most spent on the autopilot as you can't control the plane, the game suddenly settles and smooths out and I can ramp up the quality to maximum and I still have smooth game play, looking back at the GPU the picture is quite different.

Settled Game Play at Ultra QualityI have tried everything I can think of, all drivers are up to date, I have even tried the Nvidia Quadro Experience drivers.

I do have my monitor connected via a Dell Performance Dock WD19DC 240W, could this potentially be the problem? 

Or could the problem lie in the fact that MFS2020 uses DirectX11 language whereas the Nvidia RTX 3000 utilises DirectX12

Any insight or help would be greatly appreciated.