Left 4 Dead 2 GPU Analysis
Comparing Left 4 Dead 2 PC system requirements to all GPUs shows that Left 4 Dead 2 is going to need a graphics card that is capable of OpenGL 2.0.

To get the best visual graphical experience on Left 4 Dead 2, aim to have a GPU that has at least 256MB GPU RAM.

Most bottom end graphics cards currently available today, will probably allow you to play Left 4 Dead 2

We are advised that 17 year old graphics cards should be able to run Left 4 Dead 2, but there could be a few exceptions to this rule.

Note that most games do not officially support laptop graphics cards, but nowadays many laptop graphics solutions are capable of running modern games. Whether desktop graphics cards or laptop, try searching for your graphics card to compare against the Left 4 Dead 2 graphics card requirements chart below.