MP 1,1-5,1 Mac Pro 2.1 - GPU Upgrade

[CarlXuereb]

Hi

Recently I bought a Mac Pro 2.1, I was thinking of upgrading my GPU to a AMD Radeon R9 280X. According to this post (Part 6.1) https://forums.macrumors.com/thread...PBVUIttmrzJ1_3d703TcAWSUycj9xdJ76tcUR0-k7B8_k

My current specs are:
-2 x Intel Xeon Quad Core 3.0Ghz (X5365)
- 500gb HDD
-32GB 667 MHz DDR2 FB-DIMM RAM
- Nvidia GeForce 8800GT 512MB
- OSX EI Capitan 10.11.6

I look forward to hear your comments