Here is an AMD FirePro V7900 4-monitor graphics card sold which I have just tested successfully under WIndows 10  

AMD released this in May 2011 as a professional graphics card, with 2GB of 256-bit GDDR5 RAM.  It draws up to 150W TDP and requires a single 6-pin PCIe power connector.  This a single-width card with four DisplayPorts on back. There are also two CrossFire connectors on top.

This card is about 3 inches shorter than most FirePro V7900s, since it does not include the metal bracket for securing the front of the card to the inside front of a case.

 

I include only the card.  I do not include any documentation or software.

I guarantee that this item will arrive working and as described.   I offer free shipping within the U.S. and a 30 day return privilege.