For your particular setup you're quite limited in what you can do, all I'd suggest is to make sure the CPU is kept as cool as possible in order to avoid any thermal throttling, if there is an option in bios to max out boost times / current draw then max them out. Use a cut down version of windows 10 such as tiny 10 which can be found on web archive, and finally if you are able to, tweak your memory speeds / timings as much as possible. Happy hunting!