Need to get a new GPU,narrowed it down to 3,please help me pick

Here is my current rig

AMD FX-8150 3.6GHz 8-Core

Asus Sabertooth 990FX ATX AM3+

Corsair Vengeance LP 8GB (2 x 4GB) DDR3-1600

ATI X600 GPU(the 7970 i used to have died,and this was the only extra card i had)

OCZ Agility 3 60GB 2.5" SSD

Seagate Barracuda 1.5TB 3.5" 7200RPM

Western Digital 250GB 3.5" 7200RPM

Cooler Master HAF 932 Advanced ATX Full Tower

Cougar 1000W ATX12V / EPS12V

Samsung SH-224BB DVD/CD Writer

Asus Xonar DG

 

Here are the 3 i am looking at.

2x http://www.newegg.com/Product/Product.aspx?Item=N82E16814131564&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=

 

1x http://www.newegg.com/Product/Product.aspx?Item=N82E16814150686&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=

 

1xhttp://www.newegg.com/Product/Product.aspx?Item=N82E16814150706&nm_mc=AFC-C8Junction&cm_mmc=AFC-C8Junction-_-na-_-na-_-na&cm_sp=&AID=10446076&PID=3938566&SID=

This last one is the MOST i can afford to spend.

 I will be using it for gaming.

Thank you guys for the help.

I'd stay away from Crossfire. 

The 280 will of course be the fastest and be more than enough for most games at 1080p.

This 270 though:

http://www.ncixus.com/products/?usaffiliateid=1000031504&sku=91996&vpn=R9-270A-CDFC&manufacture=XFX&promoid=1016

Is an amazing deal for the price. OC it and it will be as fast or faster than the 270X and be perfect for 1080p.

Get the best you can afford. Your computer can handle any modern GPU and since you are going to be gaming you will want the most power you can afford. The 260's are out immediately. Get the 280 and look for the best deal possible might find a factory overclocked one for the same price. 

Get the 280, it's a beast.