It's over at http://www.tomshardware.com/reviews/gaming-graphics-card-review,3107.html
But this card is pretty new so my bet it will be on next month's list.
http://www.tomshardware.co.uk/nvidia-geforce-gtx-980-970-maxwell,review-33038.html
To sniff out what's different among those 4 cards you would either find reviews on the specific models or make a spreadsheet and see if you can find the differences.
Bob
Hello. I am planning to build a $1,000 gaming PC. Here it is http://pcpartpicker.com/p/fr6bTW. With this build, i was going to change the GPU to the GTX 970, but on newegg i found the GTX 970, but 5 different "versions" i guess. How do i know what is the best one and which one to buy of these? http://www.newegg.com/Product/ProductList.aspx?Submit=ENE&N=50001402&IsNodeId=1&Description=gtx%20970&bop=And&Pagesize=100&Page=1

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