ROS newby - suitability of old Thinkpad X240?

edit

I've been using an old X220 (2012?) all year as my robot brain (ie it literally sits on the robot base and runs a few ROS nodes for the onboard sensors and the base controller) without issue. For this purpose I would absolutely recommend an old Thinkpad. The only drawback in my case is the battery life, which for mine lasts only 2 hours or so if I'm running a lot of tests. I haven't tried to run RVIZ or any other graphics-related programs on it though, and my gut feeling is the older Thinkpads wouldn't be good for that.

I think you'll have some problems running gazebo and rViz. Also battery upgrade would be good, as @georgeknowlden mentioned.

I am writing this on an X230 with Ubuntu 18.04, and it's great! It handles everything really well, ROS has been written quite efficiently. As a starter piece of hardware, it will be great. I got mine for around $200 AUD.

I would HIGHLY recommend getting a larger battery pack though; as cat_in_box mentions, the battery life isn't great. Something like the following from eBay Australia.