Okay so my computer is getting outdated and without replacing the mobo, i cant really get it up to spec for audio production for a fair price. (Still got a 939 socket for the processor, DDR for ram. So its all pretty expensive.)

A while ago i had iDeneb and XP dual booting, but with my motherboard it doesnt work without an IDE hard drive, (I used an external USB HDD.) even then im not sure on the stability of hacked distros. I was looking into a getting an iMac, but as you all know theyre pretty horrifically priced.

My current PC specs are

Asus A8N-SLI Deluxe  (3 PCI, 2 PCI-E x1, 2 PCI-E x16, 4 DDR DIMM, Audio, Dual Gigabit LAN, IEEE-1394)
Dual Core AMD Opteron(tm) Processor 170 2ghz (overclocked to 2.2)
2gb RAM
ATI Radeon HD 5670 512mb
I understand there are work arounds to getting the retail version of OS X to work on specific hardware, and an intel based computer (Mines AMD).

Are there any current intel motherboards that are known to work?
I have a Radeon HD 5670 graphics card i'd like to keep using. Something with 6 usb ports minimum, firewire, PS2 ports for mouse/keyboard (if possible).
Id pick up 2x 2gb ram, another hard drive so i can dual boot again, a new DVD/RW drive, looking for a dual core 2.8ghz (minimum) if anyone has any reccomendations for that too. Id be using everything else from my computer.

I was looking at "Gigabyte GA-P55M-UD2 Intel P55 Express".