Comment 41 for bug 257894

With skim, scim-bridge, and kwin's desktop effects all disabled, I got the flickering and eventually the black screen again, so please disregard my above posts about those other packages. Sorry if I was misleading.

Since I now know for sure that those aren't the problems, I'm trying the 2.5.1 driver as suggested. Before I try building it myself, I'm going to try the backported one here:
https://launchpad.net/~intel-gfx-testing/+archive/ppa