Spec:
CPU: AMD henom II X4 810
Motherboard: Gigabyte GA-MA770T UD3P
Chipset: North bridge: AMD RX780/K10 IMC
Display: ATI Radeon HD4850
Network: Realtek RTL8111C

Everytime when at the moment of logging into the desktop environment (after splashing screen), my monitor disconnected which the notification light flash (similar to when your computer is off but screen is on) while the hard disk seemed to be still running indicated by the notification light so I might assume I succeed logged into OSX.

Try booting with VESA, type this in darwin:

-x

or

"Graphics Mode"="640x480x32@60"

to get support for your video card, check netkas site