Most online sources (Tom's hardware, Socket A, Linux, Hot Hardware and The Tech Report) have rated the Soyo Dragon plus as the best KT 266a motherboard. The only really negative comment was from SL central which mentioned that the CPU was running 10 degree C higher (at 48 degree C) than on a KT 133a board. For people running this motherboard due you see higher temp. Please note that Soyo has not yet been approved as a motherboard by AMD.
If you have an OEM CPU remember your fan comes into play big time. I have a boxed CPU and my temp is matched to my buddys PC in the same room and he has a MSI mobo also we both use shims under our Heatsinks.
Is there a device that measures your CPU temp without going into BIOS?