I’ve actually found Train Fever runs surprisingly smoothly on my thoroughly mid/low-range laptop GeForce GT 650M card, even with medium settings… so it seems it’s not quite the system-hog I thought it would be.
But I get the feeling that even then, you’ll be lucky to even get the game to load on integrated Intel graphics. I’d imagine you could conceivably get it to limp by if you have a chip with Iris Pro.
I’d strongly suggest getting a graphics card if you want to play games :-S