Hey,
I currently have been trying to get my Ati Radeon HD 2400 Pro AGP working fully in iPc 10.5.6. Despite my best efforts nothing is working. Please understand I am no hackintoshing expert and is just following guides. I have full resolution but no dual screen. For me dual screen is a must. Heres how system profiler sees my graphics card:
ATI Radeon HD 2400 XT:
Chipset Model: ATI Radeon HD 2400
Type: Display
Bus: PCI
VRAM (Total): 256 MB
Vendor: ATI (0x1002)
Device ID: 0x94c4
Revision ID: 0x0000
ROM Revision: 113-B1480A-236
EFI Driver Version: 01.00.236
Displays:
Display Connector:
Status: No display connected
Display Connector:
Status: No display connected

As I stated before is a HD 2400 Pro AGP so there must be something wrong because of how OSX sees it.

Hope you can help.