Both the Gigabye Windforce RX460 and Zotac Geforce 1050 TI Mini have been tested and work. You do have to turn Secure Boot to OFF and Legacy CSM and option roms to ON.
The 4 GIG Gigabyte RX460 and Zotac GTX 1050TI min is working without needing to MOD the system.
Installed a EVGA 1050 TI 4GB Gamer Edition( $144.00). Removed the R9 360(my son sold for $75.00). Also added a Samsung Evo 850 SSD and cooling fan. Everything else is stock. (I7 6700 2TB HD 16GB RAM) 3D mark has doubled and overall performance is awesome and stability is solid. I'm running Windows 7 64bit. Love this little computer. Good Luck!
So I will list EVGA GeForce GTX 1050 Ti GAMING, 4GB GDDR5 04G-P4-6251-KR SINGLE FAN version
as another verified card.