TonyR, You and others inspired me to bring up an Ubuntu/FreeCAD .17 system. I had a spare $110 laptop: 64bit, 2 processor, 4GB, 350GB with a broken KB; plugged in a moveable KB while I wait for the part. Had Windows 7 and I erased it. I could have used a much less capable system.
I expect I will get better perf than w/windows. I will use that to attempt rendering again.
My workflow: Study Ubuntu/Unity documentation, download and create installable USB for Ubuntu (easy), install Ubuntu (easy). 3 hrs including download of Ubuntu. Download/Install FreeCAD 17. 3 Hrs because installed .15 and had to uninstall, download, study install of app image and make shortcut.
Summary, it is fast enough, its cheap, Unity makes it familiar, installs are simple.
I will connect to DropBox for design storage.
Cost: new keyboard: 20$