My sound card is shot (stock AC97 I think) therefore I need a replacement. I would like a pretty cheap card with good sound. Does anyone have a suggestion?
High fidelity is high quality. High fidelity systems are capable of covering the full audio bandwidth with low distortion, high dynamic range and low noise. In the context of digital audio, it would have to do with accuracy and resolution, both sampling rate and bit width. It would also require algorithms that don't degrade the digital signal digitized data. Where artifacts are generated as a consequential byproduct, i.e. things like aliasing, high fidelity equipment will deal with them in an effective matter.
Garbage in, garbage out. You can probably massage an audio file with post processing to clean it up some, but if the source is bad, you're polishing a turd.