During startup, D2X-XL is checking how much RAM is available, and will never ask for more even if it could, that way forcing the system to free up memory by swapping out other applications' data for the benefit of D2X-XL. The new switch '-use_swapfile' allows d2x-xl to ask the system for as much memory as it ever wants, which will cause the operating system to swap other applications' data to disk to free up memory for D2X-XL. This will make gameplay choppy if there is not enough memory for d2x-xl itself, but will help big time if there is little RAM, yet enough for d2x-xl, and some of it is just occupied by other apps swapping the data of which wouldn't hurt while d2x-xl is running. This might be pretty helpful for people running into memory problems when trying to run D2X-XL although theoretically they should have enough RAM.