How do I fix character lag and frame fluctuation in Defense Grid - The Awakening?

The loading phase in Defense Grid was laggy due to background processes on my Kingston 16GB DDR4 2666. I tried clearing temp files, but it had no effect, leaving me stuck. I then used GamePP Resource Scheduler to set the game to real-time priority and switched to High Performance mode. GamePP baseline verification showed the frame interval dropping from 8.3-12.1ms to 5.1-6.4ms. The memory controller load stabilized, and the frame pool remained consistent.