Shiyaz

I recently got a new 1050ti ( Gigabyte gtx 1050ti 4gb windforce oc edition ). My pc is an old optiplex 780 sff. The graphic card wont fit in physically, so i bought a pcie riser and as the card requires a 6-pin connector, i bought a sata to 6 pin converter too. plugged in everything but i get "no signal" on the monitor. The fans on the card didn't turn on either. I thought my psu is not powerful enough to run the card. So i took it to a shop where they put it in a pc with 800w psu( Not a branded one though) it had a 6 pin connector so the adapter was not needed. Anyway we got the same problem there too. The monitor was showing the same error. i tried in my friends pc too and again got the same error. the common factor all the pc had was the monitor which was an old one and was forced to use an hdmi to vga converter. Is the video card damaged? or is it something else? Please Help thanks in advance and sorry for bad english.

System specs Dell optiplex 780 SFF Intel core 2 duo E8400 6 gb ram 240w psu The gtx 1050ti i have is an oc model which requires a 6-pin connector.my psu doest have one. Will i be able to run it without the 6-pin connrctor by underclocking it? Should i use an external psu to run the card? What are my best options ?pls help. Thank you.