Sound card

what is the problem?
are you experiencing buffer under-run errors?

there isnt much of a difference between using a RAM chip on the sticks of RAM that are plugged into your motherboard compared to using the RAM sticks on the soundcard.

quality programs will allow you to adjust the buffer size so there are no pauses during playback.

if you are getting pauses during audio playback.. that means your soundcard's processor isnt constantly being fed with data.
and that means you have to increase the amount of data in the buffer so that the buffer doesnt go completely empty.

its a two-stage process.
the first one is obviously the soundcard accessing the buffer to drain the buffers contents.
the second one is the audio program putting audio data into that buffer.
an advanced option would be the ability to tell the audio program to fill the buffer more often.. regardless of buffer size.
it would prevent the buffer from being completely empty.
but since this advanced option isnt usually available or easy to understand.. it's simpler to increase the buffer size.
the audio program may or may not fill the buffer at the same intervals, but the important part is that the buffer doesnt go empty.

IF you increase the buffer size and the audio still pauses during playback, that means you have a large gap in time between when the soundcard access the buffer (lets go) and goes back to the buffer.
because the actual buffer might not be empty.. but if the PCI bus doesnt allow the soundcard to go back to the buffer in time, there will be a pause in the audio.

this might be a setting on the soundcard.. or a setting in the BIOS of your motherboard.

you dont necessarily have to use any RAM to buffer at all if you can stream the audio data directly from the hard drive fast enough.