I've managed to install OS X 10.8.3 on a desktop PC with the following components:

CPU - Intel Core 2 Quad Q6600

Motherboard - ASUS P5KPL (ALC662 High Definition Audio, Atheros L1 Gigabit Ethernet)

Graphics card - Radeon HD3850

But I'm stuck at 1024x768 resolution and without sound or network access. I remember having run OS X 10.5 with full graphics, network and audio capability on the exact same hardware back in 2009. Is there a way to enable all this in Mountain Lion? Any help would be appreciated.