Yes, Im pretty sure I have seen this setting in the BIOS. On boot up press F2 to get into the BIOS. Advanced tab, speaker volume. I would presume this does what you want but you will have to try it.
On my TR2MP I think there is an option in the Notebook Setup in the Sony VAIO folder for default volume (can’t check as don’t have it to hand at moment).
This is where I miss the dial present on older models. You have to wait for windows to finish booting before one can adjust the volume….I think toshiba laptops still have that dial present.