I'm having trouble with the graphics acceleration with an intel graphics card on Debian. This is on an x250. I'm kind of surprised, because it's the first time that the intel chipsets fail me. Usually they work the best because the drivers are free.
I'm using the driver versioned at 2:2.99.917 from backports, although I see that unstable has added stuff from a recent git branch. Still, if apparently I'm using the latest released driver, shouldn't that be enough?
Have you tried removing the Intel graphics drivers? Based on "It is probably time to ditch xf86-video-intel[1]" I removed the intel drivers from a debian machine and an Arch machine and things have become more stable for me.