Concerning your first question:
- Yes your graphics card must say it supports OpenGL. But let me add that pretty much all graphics now support OpenGL these days. The issue they many openGL programmers face is not whether openGL is supported on a graphics card, but which version of openGL is supported. The most recent being openGL v2.1. [i’m ignoring version 3 cos driver support is sparse]
One nice software that I use to find out about openGL support of different graphics card is “OpenGL extension viewer”. You can download it here:
As for your second question:
2. You are wrong here. Most, if not all, onboard graphics card support openGL. On-board graphics chips, many of them based on Intel GMA series, have support ranging from openGL 1.4 all the way to openGL 2.1. I know this for a fact.
As for your last question:
3. That very simple. Simply try to create an openGL context. If it fails, well, that means you don’t really have openGL support.