Problems with Windows

[GregW]

I recently had my hard drive crash and had to have it replaced. When it was back at Dell- they installed a new hard drive and re-installed windows. Windows has been working INCREDIBLY slow. After 2 - 6 hour sessions with Dell and another shorter session- they say the computer is up to speed. It is not anywhere near as fast as i originally sent it in (before the hard drive failed). I have barely anything on the laptop- so it is not a virus.
Any programs to try and get the computer running up to speed again?
It has a I7 and 8 GB of ram and is running on the high performance mode. Still crawling. Any ideas for programs to download or anything to get it running right?