Our Rovers do not have computers inside them but the R&D Payloads do. We recommend that all new customers purchase an R&D Payload which comes pre-loaded with ROS and allows you to drive the robot around with a controller within 5 minutes of unboxing.
Want to use your own computer? No problem, just check out the rover tools on our GitHub page. Follow the readme and the menu options for install and the rest will be handled by the tool. This is the same tool we use at our production facility in Minnesota so it is always up to date.