Problem with my sound card uninstalling upon startup in win98

[snuh]

i have a soundblaster 16 card for my pc - an amd k6-2 board - with a
550 processor. every time i shutdown the computer, the card kicks out.
when i restart the computer, the computer gets to the windows 98
screen and stalls for about 5 minutes and then restarts in safe mode.
in control panel, the sound card has a yello question mark beside it,
saying there were problems with it on starting, generic error message.
ive followed all instructions that the computer suggests to no avail.
if i unistall the card in control panel manually before i shutdown,
the computer starts fine, and then re-install the driver upon reboot.
however, when asked if i want to restart the computer to finish
installation, i have to say no, the sound icon appears in the system
tray and the sound works fine. ive tried the card in both slots.
everything workd just fine until about 7 months ago i hada virus on my
computer and i was forced to format every drive - ever since then, the
card gradually began to have trouble upon startup.

but the soundcard works. what could the problem be? and better yet,
the solution?