You can try with a 650 TI 110W as it has the external power connector for 75W leaving 35W to draw from the slot, if the power supply has the 6 pin connector it might get enough from the board and the external to run. Alas there is no 6 pin available. someone tried the 8 pin eps to 6 pin pci connector without success using a 960 120W.
https://www.dell.com/community/PowerEdge-Hardware-General/Adding-GPU-to-Poweredge-T310/td-p/6117847
https://www.dell.com/community/PowerEdge-Hardware-General/Graphics-Poweredge-T310/td-p/3617003
At least someone has run a 40W card in the system, so the 30W 1030 may be an option.
Seeing the psu connectors I see why the eps 8pin converter four black and four yellow failed, the psu has four black two yellow and the two red pins are only 5V. It has 24 pin and 4 pin for motherboard power, and 2 sata connectors, and the 8 pin drive connector for the hot swap drive cage isn't eps power
Sometimes converting a server is easy, other times it takes some hacks to make things work.