A month or two ago I was building up a Lenovo m910T desktop. Maxed out the CPU, RAM and tossed in a NVME.
I wanted to use a GPU but the system had a 180watt power supply. Tried to use a ATX power supply but the 12VO to ATX adapter just doesn’t work. However I found on eBay the FSP600-60AGPAA power supply. It’s a 600watt 12VO power supply and even has the PCI-E power cables.
Fits perfectly in the case and no modifications had to be made. Running my RTX 2070 Super just fine. The fan in the power supply is a bit loud but I am fine with that. However if it gets louder I will toss in a Noctua fan in it.