hd 4000 has issues with some displays.... have you tried to see if an external monitor has acceleration? also they just released a new chameleon version that you can specify the framebuffer id's starting from 0 to 11
IntelCapriFB= For Intel HD 4xxx, range 0-11
http://forge.voodooprojects.org/p/chameleon/source/commit/2261/
here is a list of AAPL,ig-platform-id's. chameleon simplified it and just uses the last digit
http://blog.stuffedcow.net/2012/07/intel-hd4000-qeci-acceleration/