trouble with 4890 in new install

[clarknova]

Greetings,

 

It's my first post here, please go easy!

 

First, my hardware:

 

Tyan S7025WAGM2NR (5520 chipset, I think), onboard video

Dual Xeon 5520

12GB triple-channel DDR3

Intel G2 80 GB SSD

XFX Radeon HD 4890 video card

 

What I've managed so far (it's been a long haul, so I may be forgetting some important details):

 

Install Snow Leopard and Chameleon bootloader using [url="http://www.insanelymac.com/forum/topic/279450-why-insanelymac-does-not-support-tonymacx86/"]#####[/url]

modified a file (plist?) to get the intel GBE working

booting 64-bit kernel

updated to 10.6.4

 

So far so good, but I'm having a heck of a time with the vid card. I've tried a few things, and at various times it has stuck at the apple logo splash screen eternally with no hdd activity, or kernel panicked, or, at present, no hdd activity or video output at all after the POST screen. I don't even see the BIOS.

 

I fankly don't remember everything I've tried to get it working, but here's what I tried most recently:

 

I booted without the card in, using onboard video.

Downloaded the 10.6.4 ATI patch fom netkas.org and installed it.

Ran Kext Helper (I think) which I must have installed previously. I believe it indicated while running that it was updating permissions.

Put in the video card--no bootloader.

 

So here I sit. I'm sure I missed something obvious, but I'm still quite unfamiliar with the ways of osx86. I've done a lot of reading and tried a lot of things to the point that I've pretty much confused myself.

 

Some help please?