I'm not sure what exactly you have changed, I have an nVidia graphic card (GTX770) with nVidia propietary drivers and the HUD is showing for me with the stable graphic engine "SSG".
Are you sure you did not have changed the Speed-Dreams graphic engine from "SSG" to "OSG"?
OSG is the new experimental one, it does look better but has no HUD in 2.2.0 (some work have been done for it in the development version trought).