Graphics card advice needed

If you have the money for the 7970, you might as well go for that and then Crossfire later.

Yet you are definitely going to need a new power supply for your Dell, as the one in there is not going to run a 7970.

I'm planning on upgrading to at least a 650W but my budget for the graphics card are about 500$ so I don't have enough to crossfire the 7970 and by the time i'll have the extra money for another 7970 the 8xxx series will be out.

I don't think that Dell board will support crossfire.

No need to upgrade every generation. I think a single 7870 would be the most sensible option, especially if you are only pushing a single 1080p monitor. Only the 7900 series officially supports 3-way and 4-way crossfire.

But, of the choices presented, go with the 7970. It's usually better to a single more powerful card vs a pair of cards because of all the technical issues that accompany it; heat, drivers, games that don't utilize it, power consumption, micro-stuttering, etc.

I'm currently working towards replacing almost everything on my current build the only reason I got the XPS 8500 is because my cousin does reviews on pc parts and he sold it to me pretty cheap. I will be replacing the mobo will a ASUS P8Z77-V LE PLUS. The only thing I will be taking over to my new build is the i7 3770k CPU.

I know there is no need to upgrade every series but I was thinking of getting the 7850 in CF because I will only be doing 1 monitor at 1080 and that will play any game that I want and do everything else that I need and it would be a lot cheaper than the CF 7970's.

Yes, but wouldn't you rather have 1 7970 and then CF it later? And you still need a power supply. If you're just doing one monitor, you don't need more than a 7870 or a 7950.

Why waste money on a new motherboard?

Got anything better?  

I have to move to a new case because the xps case has a irregular psu area which I need to change to get a better GPU and in getting a different case the Dell mobo isn't a ATX board.

Anything better as in a better mobo?

The Dell mobo is a micro-ATX form factor.

Honestly I think its kind of a waste of money. I also don't think you have the K-version, as Dell doesn't usually put the unlocked versions in their computers.

It is a k because I got my computer right after release and the k was the only one that they had yet (the day of the release).