Welcome to DH, and I appologize for your not getting support.
The SM Bus has to do with your motherboard, so you will need chipset drivers. If you bought the PC with Vista, we are seeing there are no applicable chipset drivers available from the manufacturer. One of our members has posted some drivers, however whether they work for you model is a crapshoot.
Check out the thread
here, and good luck.
If they don't work, you might want to shoot a nasty letter to Toshiba. This problem is all over, and its inexcusable.