Unity 2D performance on an actual netbook with working Intel 945 graphics, using 256 MB of shared video memory: bad. Menus lag, window contents are slow to render, etc. Unity 2D performance on a QEMU-KVM virtual machine, emulating an ancient Cirrus video card with 4 MB of video memory: excellent. There's no lag anywhere. What's wrong here? Are the Intel graphics drivers that bad? Is shared video memory that much of a liability? Does KVM do something behind the scenes to buff up the emulated video card? What gives?