It's not just gpu/driver, it's library versions, compile flags, compiler versions plus all the flags (static and dynamic). Let's say 50 options. If it costs $

It's not just gpu/driver, it's library versions, compile flags, compiler versions plus all the flags (static and dynamic). Let's say 50 options. If it costs $1 to test each combo it would cost 2^50, around $10^15 dollars. Google only made $10^9 dollars profit last year. Now of course I'm being facetious but do not underestimate the cost of testing.