You can't play *proper* games for desktop VR on Google Cardboard. You can however use a Google cardboard based VR as a 'display' for your pc

 

There's also Samsung Gear VR, a cheap head mount which uses a Samsung phone as a display.

Just note that cheaper VR solutions uses much lower resolutions, gets less framerates, and do nothing to help with the VR nausea sensation this first generation of VR gives. The expensive VR solutions do their best to help with that to give a more satisfying VR experience.