No, if GPU no fans installed only block you can't use without watercooling.
 
You should show us card, if that's real Hydro Copper than you will need something like this to work.
 
https://www.ebay.com/itm/GeForce-GTX-780-3GB-Graphic-Card-Cooler-Only-Working/302886832608?hash=item46857649e0:g:zb0AAOSwzT9bn6yD:rk:1:pf:0
 
or you can find somewhere ACX Cooler for GTX780Ti.
GTX780Ti is great card. I would still use my 780Ti K|NGP|N but I didn't had waterblock and it was to much to pay shipping and waterblock would cost me almost as new block for GTX1080Ti. With GTX780 Classy waterblock I would stay on GTX780Ti until 2020.
What my GTX780Ti K|NGP|N 1500 points higher graphic score than GTX1060. 
GTX1060 Pascal is still one of most used graphic cards with high class computer.
Bigger percent of gamers no money to even close to GTX1080Ti or similar cards or RTX2080 series.
I could use GTX780Ti K|NGP|N 5 years and every time to have 60fps on 1080p max settings, only to avoid some specific games who need more memory. But I couldn't use with default cooler and I was afraid if she die in moment when I don't see nice option on market and RTX2080Ti is still not so old to become cheaper.