Thanks for your replies.
Johan K: Option "FrameBufferCompression" does not seem to play any role: it is not recognized as an available option by the driver I use (intel).
analytic_kernel: Note that using Intel integrated graphics I don't have any opengl option but xorg-x11,
Concerning hardware, I perfectly run dominions 3 in windows vista on the same machine (it's pretty slow anyway, slower than when it worked on Linux) but I don't use vista at all and I want my preferred game on linux again. Memory is probably not an issue: the system is rather stable, I can run it for DAYS, with relatively high CPU usage and without problems. I can play other games (with and without wine simulation), watch movies, compile for hours, and I don't get a crash... apart when I try to run dom3
Now I'm reinstalling dom3 and I'm burning the last Ubuntu to see if it's able to run it without problems. Then probably I'll try ramarren's configuration.