This is how it looks like with multiple windows, the performance is cut in a very linear fashion
- windows: 60fps | 16.7ms
- windows: 30fps | 33.3ms
- windows: 20fps | 50.0ms
- windows: 15fps | 66.7ms
- it does not seem to matter how many monitors are involved
- it does not seem to matter which window is in focus
- this also affects the PIE mode
- the editor’s ‘Use Less CPU when in Background’ setting does not affect this behaviour
tested on:
3570k @ 4GHz, 16GB, 7970 3GB, Win10 64b