I don't understand the point of this thread. The 6990 generally eeks out a tiny win over the 590 at max resolution. Besides that they are very comparable.
Is there a reason you (OP) want to compare them?
Just when you think you've made a good arguement one way or another someone will always find a benchmark that contradicts what you've posted with your own benchmark. Let's just call both cards equal and call it a day
afaik both cards have been discontinued or will be discontinued soon to make room for new 7990 and kepler's dual gpu cards. those cards were overkill for many people.