Cisco c250 M2 and a Radeon 3400

yourepicfailure

Recently, someone I know obtained a retired Cisco C250 M2 server. He's trying to set it up for Blender and other 3D rendering. However, it's junker on board is some of the worst I've seen. However, he obtained a Radeon 3400 from a computer that was about to be destroyed, and can confirm it's working.

The server has two risers that produce 2 Pciex16 on one and a Pcie x16, x8, and x4 on another. The graphics adapter is an x8, so I loaded it up into an x16 slot, mainly because I wasn't feeling up to the task of removing the frame plate to fit in the low-profile x8 slot.
It booted up, but then I had to restart to "Apply Changes" for server 2008. Now on boot, it hangs on the "Configuring and testing platform hardware" stage, unless I remove the card. This takes place on bios startup, not on loading Server 2008.
I moved it to the other x16, still the same issue. Moved it to the x8, still same issue. I've read that past cisco servers have a whitelist, however any documentation mentions servers other than this one.

Anyone know what the problem could be? I ruled out memory because I pulled out 4 faulty sticks earlier today. And it still booted up once before with the card. Thanks.

TCPMeta

I would think it's the power supply. I've had issues like this before when the system will lock up in post or doesn't turn on at all. Just the video card alone from what I found needs at lest 550watts. Also that chipset is typically a PCI-E 16x.