Lol yeah gotta say it, everything sounds messed up
Quick message b4 i head to bed, 02:30 here, to find the power lead, im not too sure what kinda power lead attaches to AGP, on my PCIE its a different one than ive seen on some AGP's.
Basically u need to find what plugs into the card, then trace it back to the Power supply. Make sure if possible, that nothing else is plugged into the same cable, ie splitters like u said. If the cable only supplies power to ur card then we will at least know what we r doing that right
As for the error, i think its to do with the soundcard. Have u installed or changed anything to make this happen?
Hopefully someone else can help more!