I continually try to upgrade my home system when money is available and I've decided to replace my current 9800gtx+ with a Radeon gpu to compliment my 1090 CPU and ssd. I have the 890fxa-gd70 mobo but it only supports 2.0x16 which I don't believe will work with the newer HD6000 Radeon cards. I'd also like to later use crossfire to link two gpus, so what would be the best card to do so. I'd want to spend under $400 for one gpu. Thanks.