Hello, I'm going to upgrade my GPU, and a couple of days ago the Matrix 7970 became available... the thing is I'll be playing on 1080p mainly, and there are the radeon 8xxx rumors already... The thing is, if I buy a cheaper card (7870) I'll definitely need to upgrade again in a couple of generations, would the 7970 stay REALLY strong for at least 3 years, or would I need to upgrade almost as fast as with the 7870??