Alright, I may have a limited understanding of the my computer inner workings (other than WOO ELECTRONS), but this was a weird problem that vexed me. If anyone else has run into it, this may help you.

Otherwise, whoops.

Anyway, I installed OS X 10.6 and got everything working nearly flawlessly--only one problem: when my computer attempted to wake up from sleep, the monitor wouldn't display anything when it resumed. I thought it was in my kexts, my DSDT.aml, or the bootloader. Nope, nope, and nope.

Brief systems diagram: (brief): ATI Radeon HD 4870 -> DVI port (VGA adapter) -> VGA slot on my LG flatron L227WTG.

That was the problem. I used a DVI cable and put it in the digital port on the monitor and sleep works. Weird.

hopefully it'll save someone a headache!