Computer doesn’t boot but fans turn after changing graphics card

Ok, I have a computer that I built 5 years ago, it was working ok but I was starting to have issues that I knew were related to the graphics card like gta V freezing and cities skylines etc. So I decided to change the graphics card with an other one a friend had given me. But then, I tried to turn on the computer after I had changed the graphics card, but the computer would not boot but the fans were working. I tried multiple things like checking the power was well connected, rebooting the computer, using HDMI instead of DVI. But nothing worked. After that I tried putting back the old graphics card to see if it would go back to normal but it didn’t.

So please I need help!

Specs: i7 4790k
16gb ram ddr3
B85-G41 msi motherboard
Corsair cx600m (600 watt) powersupply
Old graphics card: amd Radeon r9 270 2gb
Other (newer) graphics card: nvidia gtx 960 2gb


Other notes: I suspect that the gtx 960 may have been exposed to static
Also I cleared all the graphics drivers from the computer before doing this.
And when I try to boot the computer now it stays on for a few minutes, then turns off and on again and waits a few seconds does that again and stays on.
 
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