I understand this is late... but if someone needs it.
Do not compress your files, ever. If you did, back up, reformat, and reinstall.
Do not have your drive's contents indexed during idle time.
Turn all all unnecessary sharing to the files, folders, ddrives, volumes, system. Turn of "previous versions" and have another program do your backup routine (but get it done!)
On Windows, turn off all your services you don't use, uninstall everything you don't need, keep all your drivers up to date. Don't bother with a pre-caching software, WinNT kernels do fine on their own.
But all your apps and heavily trafficked data on a SYSTEM or BOOT driver, and then a DATA driver, should better yet, be a whole other physical volume