New GPU isnt displaying but old one is???

Hello
I just got a new RX 570 GPU from gigabyte and I go to pop it into my computer an i5 2500 with 16gb ram windows 7 and it isn’t displaying anything no keyboard or mouse power comes on. but here is the weird thing when I go to pop in my old GPU an Nvidia 710 ( a piece of ****) it works fine. this is the second 570 I have used because I returned the first one. I have tried a lot of things but I am stuck someone please help