Linux Version in Alpha?

Especially when we talk about OpenGL-based game. GLSL doesn't have anything like "Shader Model" at all.
It's possible to compare different APIs, but technically it will be wrong.

The only thing out of these whose measurement is somehow correct is GB for Ram. The CPU speed says just as much as DX9: nothing.
An old computer with a Radeon X800 and a Pentium 4 with 3,97Ghz (man that's more than my current i5 has!, damn why did I ever change my cpu) fit those specs, but they are totally useless to play PA.

A way better way to specify this would be to say: CPU type X or similar, graphics card Y or similar.
Many ppl won't know what card is similar to what card, but it can be looked up. Just the information "3Ghz" can mean very different things. Games from 5 years ago already asked for 3Ghz and DX9.