Also those drivers are huge (really, HUGE) and have incorporated pieces of code with widely differing IPs, patents previous companies and other sources for which opensourcing would probably be a major legal hassle and lawsuit risk.
Also... if you're nVidia / ATi... what's the gain in giving optimization paths and software optimization database to the competitor? Those drivers are full of application / game specific optimizations to make them look better / run faster / workaround bugs.
Also those drivers are huge (really, HUGE) and have incorporated pieces of code with widely differing IPs, patents previous companies and other sources for which opensourcing would probably be a major legal hassle and lawsuit risk.
Also... if you're nVidia / ATi... what's the gain in giving optimization paths and software optimization database to the competitor? Those drivers are full of application / game specific optimizations to make them look better / run faster / workaround bugs.