I have been out of mining for awhile for btc and ltc and it is time to clear out some old stuff

i have 2 r9 280x and 3 7970

http://www.newegg.com/Product/Product.aspx?Item=N82E16814161412
http://www.newegg.com/Product/Product.aspx?Item=N82E16814121499R
the other 7970 is a diamond reference card


http://www.newegg.com/Product/Product.aspx?Item=N82E16814202061

they are used but I don't know what a fair price is for them