I want to add a temp sensor to my 9800pro, but i dont even know if its doable, considering i dont even know if theres anywhere in the board to plug into, or to solder to, etc
you may want to try looking on xtremesystems.org for something of that nature. I added one to my 9600xt, but there was already a spot on the pcb for it. I just had to add the components and flash a bios that supported the thermal monitoring.
the chip was an lm63, which is VERY simple to hook up to the SMBUS.