On my end, I`m pretty sure it`s the 2GB VRAM of my integrated GPU that causes the Vulkan issues, as you suggested.
Nevertheless, with the old drivers it runs well, with newer or current ones, Vulkan crashes. I limit myself to the stock sceneries or official paid ones, but not Orbx, since I have the impressum that the stock sceneries are more optimized.
I`m currently flying in the Colorado region, and with the newest drivers, I can fly to and from airports, but not from others.
Like, I managed to fly in Vulkan from Aspen to Gunnison Crested a couple of days ago. Today, I can`t spawn at Gunnison with Vulkan (CTD), OpenGL runs. Sometimes it helps to load the setting in OpenGL, go back to the menu and switch to Vulkan, but this did not work today.
- 1600x900 60Hz, frame rate limit off (I get around 40-50 best anyway)
- no HQ anti-aliasing
- texture, terrain mesh and terrain image quality set to medium, rest to low
- Asus ZenBook UM433 / 16 GB RAM / 1 TB SSD / AMD Ryzen 7 3700U / 2.3 GhZ / AMD Radeon RX Vega 10 integrated GPU
Again, with the OEM drivers that came with the NB, Vulkan worked, and also with 20.9.2 AMD drivers. Unfortunately, with an updated OEM driver and newer drivers from AMD directly, Vulkan crashes randomly.