Wow, I spent an hour or two finding LSPCI, and all along I had it. ;) I guess my card is Intel Corporation Mobile GM965/GL960 Integrated Graphics Controller, if that's what I'm looking at. And it's not just GMod, but Portal also doesn't work, if that's worth anything. On Windows, a few weeks ago, I went to the Intel homepage and it auto-detected my card and upgraded it. After that, everything worked. Another piece of information.
