Older models like this won't take a radeon R series so you are limited to NVIDIA cards up to PASCAL.

Newer cards like the RTX 2060 2080 won't work for the same reasons.

Lowest model I would recommend is GTX 1050.

There will be few issues with that but you should remove any ATI Drivers BEFORE changing cards.

The other issue is that VGA and analog audio are gone.

so you use a Rocstor Premium HDMI/VGA adapter Y10C119-W1

https://www.amazon.com/Rocstor-Premium-Video-Cable-Y10C119-W1/dp/B01N9W4RVH/

https://www.amazon.com/Gigabyte-Geforce-GDDR5-Graphic-GV-N1050OC-2GD/dp/B01MG0733A/

For a bit more a 4 gig 1050 TI is also a good option

https://www.amazon.com/ZOTAC-GeForce-DisplayPort-128-bit-ZT-P10510A-10L/dp/B01MCU1ERO/

Lowest I would recommend is a GT1030

https://www.amazon.com/ZOTAC-GeForce-DirectX-Profile-ZT-P10300A-10L/dp/B0711NWFJX/

https://www.youtube.com/watch?v=BUOrnp2PjK4

Thanks a bunch.  I will say I updated the driver on my AMD and in device management it changed the name of the card (now AMD Radeon HD 6770).  But WOW is running better.  Have you seen this before? Or should I still try to upgrade?