Galaxy s2 won't stay connected on laptop?

When I connect my galaxy s2 to my laptop, it just keeps connecting and disconnecting. I have downloaded the drivers on my laptop. I've tried it on another laptop and it connects fine, but not on the one i have. How can i fix this?

The laptop i'm using is a lenovo y410p and has windows 8, the one it worked on is an hp g6 with windows 7

Sounds like a short in the usb port or cable.

Change another cable, try another usb port or install driver in your laptop