No surprise, but thanks for taking the trouble. However I forgot you had updated Xorg, as intellegacy was probably built for xorg-x11-server 1.8, probably little or no chance of it working.
Have been reading internet stuff on glxgears and “intel” driver. The FPS slowdown could be due to KMS/DRI2 with some blaming DRI2 since more challenging 3D games are affected. Most agreed that glxgears is too simple a 3D rendering to be useful as a benchmark. Intel driver developers will not accept it as evidence of a problem. In any case, they are busy sorting the backlog, like the bug probably affecting you and other Arrandale owners.
Good luck for your remaining tests with the latest version of “intel” driver.