Pardon me if this question is a little inappropriate. I have been using onboard sound since the first day I touched computer. I always plug it in with my ALTEC LANSEC (1 bass, 2 speakers) that has been bought for about a decade now.
So I'm curious. If I buy myself a sound card, what are some of the benefits I'll be getting? Will the quality of sound be crystal clearer than the onboard? Are there any other benefit?
There are a million threads on this topic. On Vista or 7 feature-wise there will be no difference but the sound card may be bundled with useful software like media creation/dvd playback, etc.
Onboard sound has a lower performing pre-amp. You will get an improvement on your Altec Lansing, yes, but mainly because your speakers aren't very good--the pre-amp on your speakers are bad and you can't add significant gain without distortion, so you are "making it up" from the sound card. In reality the solution is to get better speakers.
what astralite said. your greatest benefits from the addition of a sound card would come to you if you had more 'active' needs either in terms of working with external source material - specially if it's analog - or if you wanted to venture into building your own cheap home studio to record music. pro-audio sound cards offer expanded inputs / outputs, digital/analog converters and basically the capability to do more with external sources. However, these days the sample rates that were once the dominion of high end sound cards are pretty common on 21st century motherboards.
i'd think through what you really want to achieve before jumping into anything. even if, for instance, you started making recordings and wanted to get those onto your hard drive to edit, etc., most of the new portable audio recorders - essentially replacements of DAT recorders and minidiscs - rely on the same sd card storage technology you use in a camera - and this includes audio industry mainstays like tascam as well - so it's hard for me to recommend a card to you even if your uses were more more highly specialized.
as astralite suggested, concentrate on other components if all that you're really after is better listening experience. it's a great time for budget audio gear -much to the chagrin of those of us who have spent small fortunes in our lifetime - and really fine sound can be achieved on a modest budget. the first thing i always did was throw out the speakers that came with pc systems back in the day. times have changed.