We don't help people run proprietary games here.
> Supertuxkart = clone of MarioKart
Nope. They don't use the same engines and have different game mechanics and
tracks.
> xonotic = clone of quake 3?
No, not at all. Xonotic isn't even a clone of CPMA (Challenge Pro Mode Arena,
a mod of Quake 3 Arena); it's its own game with its unique
Okay, I apologize.
Back on topic: Intel graphics will be slower on Trisquel than on other
(non-fully-libre) distributions because we don't ship microcode updates.
Expect a 30% performance loss.
To be more accurate, I think the distributions (Debian, Fedora) ship it in
the form of packages.
As I wrote: "if old hardware does not work with a recent Linux-libre kernel,
then it probably cannot work with free software". If there would exist a
(reasonably stable) free firmware, it would probably be in Linux-libre.
Recommending or supporting non-free software is against our community
guidelines (it is not "helping" you to make you surrender your freedoms):
https://trisquel.info/en/wiki/trisquel-community-guidelines
Steam is proprietary software. Whose "raison d'ĂȘtre" is to impose
restrictions (DRMs)