I have a Scan 3XS system with a 600 Wpower supply and an Nvidia GTX 760 graphics card in it. I'm currently looking to upgrade the card, probably with a 1070, and I have a couple of questions:

1. Can I just buy any 1070 card and replace the 760, or are there some interface/connections considerations that might trip me up?

2. The 1070 cards I have seen differ in value by up to 100. Is there any significant difference between the different cards, or is the cheapest likely to be best value for money?

Any help or advice greatly appreciated!