You definately making progress!
I found another potential tweak. I was testing it for superpi but it actually made times worse (compared to just killing explorer shell altogether). Its a replacement for the explorer shell of windows. I was using LiteShell but there are many variants that have different features. Unfortuantely I dont have alot of spare time right now to test things, due to making 2 websites and some other crap. I have no idea if it would affect pcmark though. Just do a google search for explorer shell replacement or go
here