Why is everything running so slowly after I formatted my laptop?

I had some viruses on my laptop, namely a Google redirect, so I used System Recovery and started anew. I reinstalled some programs (Steam, Adobe and Microsoft Office suites) and tried it out. Everything seemed to run slower; I got higher ping when playing online video games, there were pauses between clicking between menus, even dragging a window around sometimes looked like a slideshow. Restarting didn't help. What's going on?! Serious answers needed!