My asus cg5270 wont run a radeon graphics card

[TyRedbullTy]

Hello, I don't have a wide range of knowledge about computers but My Asus CG5270, running on Windows Vista, will not run a Radeon x1950xtx PCIE 512M( Got that from the back serial number). The screen doesn't even turn on when I put the graphics card into my computer. Any suggestions?

 

[mdd1963]

Is the gpu's external power input(s) connected? card fully seated? is the PSU sufficient?