Hardware blitpipe = OpenGL or MediaCore. Most likely it's sufficient to turn off the Accelerate ... panels option in the prefs instead of the whole OpenGL stuff. Possibly a system update messed with things... What Sources and effects do you use?
I'll try turning off OpenGL. You mention sources, and it got me thinking. I think it's somehow related to ProRes 4444 and Genarts Sapphire plug-ins. Using both of those in the same comp seems like it raises the chances of this Blitpipe crash.
Ah yes. Could well be. ProRes is hardware accelerated, after all and may interfere with AE's own stuff.