^^ 6850 is more future proof and is better at tesselation than 5770 too. So adding 1-1.5k by saving up is a no brainer. Try sapphire 6850 standard edition. Should be within 10k. Or wait for nvidia gts 550. If its within 10k and perfoms good, then grab it. Even if its priced a little higher and gives a tad better performance than 6850 or gtx 460, it will push their prices down.
So wait a bit more, atleast till this month's end and believe me, its going to be worth the wait.Don't go for 5770 now at 8k. Makes no sense. It would had been a sensible buy, 2-3months back, but not anymore.