So...after the power came back on and I returned home, I went back to digging for more info on that 5800C chip....here's a google translated page to probably the closest thing I've seen to a datasheet for that chip:
http://en.pudn.com/downloads159/sour...716740_en.html
Best I can guess is it's made by MTK...but searching for MTK 5800C yields nothing. The best I can figure out...MTK is Mediatek which I know makes a bunch of DVD player chips (I've had 6 DVD players...all with essentialy MTK SoCs)...but they also make stuff for HDTV and GPS...they bought Analog Devices Othello and SoftBand products and now make cell-phone chips too. Thier webiste doesn't mention ANYTHING about thier parts. So, the mystery is solved...somewhat...
I'd still like to find my DAC...but I'm not removing the LCD to do it.