Replying to myself is bad form, but I decided to run some more tests. This is at Flightbeam’s KSFO, in the (unsupported and not optimized) PMDG 737-800, spawned in on Runway 28L, using Live Weather. TAA, most settings on High, Volumetric Clouds on Ultra, airport and air traffic turned off. Frame Generation enabled. For all of these tests, I do also have a second 1080p monitor being driven off the same card with email, Discord and Task Manager running on it.
VRAM usage is under 9.5GB:
Now, using the sim’s Ultra preset across the board (which also spawns in AI airport traffic). VRAM increases to 11.3GB and performance decreases as expected.
Now, the worst case I can personally rest without a new monitor - Ultra settings, again TAA but render scale set to 200%. That is an effective rendering resolution of 5120 x 2880, and substantially more pixels than straight 4K. VRAM is now 15.3GB and my framerates have dropped as the resolution has increased.
In flight, a few thousand feet over the western edge of the Bay area, VRAM has decreased by under a 100MB, still just under 15.3GB:
I then paused the sim and changed my Render Scale back to 100%. NOTE THAT VRAM DROPS INSTANTLY, as it should, to just a hair over 11GB:
Resetting my sim to my pre-test settings, including disabling Airport and Air traffic, and my VRAM has - again - dropped further to its usual range, or about 10.8GB:
NOTE: I briefly had even higher VRAM use, nearly 15.9GB, but oddly enough that was with clear skies preset sitting on the runway, because I had forgotten to turn on live weather. I would have expected weather and cloud cover to have increased VRAM usage, but in fact, it was quite the opposite:
