I need to find out how my hard drive is down to 70 GB. After Windows install, it's about 460. Since then, there's been plenty of stuff installed, but all I can account for is 205 GB of Steam games, 30 GB in Origin, and the largest folder in any of the Libraries is 20GB. How do I account for the other 90GB? Nobody is using any sort of massive programming or multimedia suite, so how do I figure out what's using up all that space?