How do I know if my video card can run Unity?

This isn't a full answer but a good place to start including the link at the bottom. http://www.inalogic.com/component/content/article/34-general/63-demystifying-unitys-graphics-hardware-requirements

So you can run

 /usr/lib/nux/unity_support_test -p  

which should give you some detailed output about Unity's requirements and if they are met, e.g.:

OpenGL vendor string:   NVIDIA Corporation
OpenGL renderer string: GeForce 6600 GT/PCI/SSE2/3DNOW!
OpenGL version string:  2.1.2 NVIDIA 270.30

Not software rendered:    yes
Not blacklisted:          yes
GLX fbconfig:             yes
GLX texture from pixmap:  yes
GL npot or rect textures: yes
GL vertex program:        yes
GL fragment program:      yes
GL vertex buffer object:  yes
GL framebuffer object:    yes
GL version is 1.4+:       yes

Unity supported:          yes

(Note, this graphics card is six years old and I'm having no performance problems running Unity.)

Though as an anecdote I have tried unity-2d on an old laptop with a substandard graphics card (Dell D600) and to be honest I still like it. I'm not saying everyone will love the switch to Unity, but I have decided to give it a go in whatever form I can and see if I grow to like it, so far I really do.

• Hardware Requirements
• Wiki page with more information

• You download a live CD and test it.
• You visit linux on laptops and read for your model, if somebody tried and succeeded

Well you can go to unity.ubuntu.com and check the minimum requirements for unity. If you have an intel card, the minimum is the i945 and i965. Old ATi cards provide a much better performance than their Intel counterparts, Nvidia cards can pretty much handle unity 3d pretty well. Hope this works for you