Need some help, replacing an iMac video card

[jonsmodding]

Here is the info about the machine:

Model Name: iMac

Model Identifier: iMac7,1

Processor Name: Intel Core 2 Duo

Processor Speed: 2.4 GHz

Number Of Processors: 1

Total Number Of Cores: 2

L2 Cache (per processor): 4 MB

Memory: 2 GB

Bus Speed: 800 MHz

Boot ROM Version: IM71.007A.B03

SMC Version: 1.21f4

EFI: 64-bit

 

Here is the problem and story.

Ok, i bought a vesa mount and hung the imac on the wall. After hanging it i plugged it in and powered it on. The apple logo came on, i smelled something bad (like burning electronics), the screen began to flicker, smoke came from the vents and then the screen went black and the computer turned off. Long story short when i opened the case i noticed that hanging it on the wall caused some stress and it shorted out on the video card. I THINK this is a ATI Radeon 2600 PRO but need someone to confirm.

I have a ATI Radeon HD 2400 XT brand new in its box, it is original apple and never used so i know its good.

The computer logic board and all other components are definitely good, i removed the logic board and all components from the case, and disconnected the screen. i have the computer hooked up and running, it will power on and go to target disk mode.

IF you swap the heat syncs from my original (ruined) video card with the 2400XT then it fits perfectly into the video card slot of the logic board. When i put in the 2400XT it will boot but will not show video, i do not have the original screen that connects directly to the logic board, i have a hdtv connected via the external monitor cord.

 

What i am looking for is a fix or driver or something that will allow my iMac to work with the downgraded 2400xt card.

Any and all help is greatly appreciated.

 

 

-Jon