Hmm, I'm not quite sure what you mean about giving the sound card more memory but I'll take your word for it
The system is built for music production and the sound card has it's own processor/s for use with effects, an on board synthesiser and a sampler.
Depending on the environment you're working in and the load on the cpu, ram and hardrives, you can choose to load more sound into the ram, as opposed for it to be read from the hardrive.
If for example you have a large number of audio files being read from the hard drive, it may start to crack or pop, because the hard drive has hit it's limit.
So what you can do is tell the sampler to either, read ahead further (load more into the ram, slightly increasing cpu load, and lowering HD load), or load some or all sounds entirely into the ram, increasing use of soundcard processor, but significantly lowering HD usage and giving you the quality back and a little room to play with elsewhere.