Hey,
I think sound doesn’t work because you have no drivers installed therefore and also for SM bus controller you have to download the driver on Toshiba page.
http://eu.computers.toshiba-europe.com > Support & Downloads > Download Drivers
Archive > Equium (Notebooks) > Equium L Series > Equium L40 > PSL41E
But you will see that there are no XP drivers available but what you can do is using the PSL49E model number that supports Windows XP. Usually there is no big difference between these models and the drivers should work on your system too.
For SM bus controller you have to install the chipset driver and for sound card the sound driver but latter requires Service Pack 3.