How to test graphics cards without a compatible PSU?

I've recently been given five Nvidia Quadro 4000 graphics cards.

However, I am uncertain wether they are in proper working condition. 3 are labeled as "defect", but I suspect this could be an easy to fix issue.

I've considered simply plugging them in my own PC, but my PSU's cables are not compatible with the coectors on the cards.

How would it be possible to test these cards?

I've considered going to a computer shop and paying them a fee, but since there is a possibility all 5 cards might be dead, I'd rather not put too much money towards doing so.