in response to Miracle1980, these options are fine for bitperfect play, they have no effect on bits, its more about performance and removing electrical noise (extremely small effect in most cases... if any is even provable. Without audio playing I can just barely hear my hard drive but its there, although I never noticed it when something is playing.)
to achieve "ram play" you could use "Play files from memory instead of disk" as it does play from ram obviously, but it has also already done decoding, so actually either work, as "Load files to memory at the start of playback" is also "ram play" except it hasnt already decoded the entire file to even more memory.
Either case removes hard drive noise, but "Play files..." reduces some noise from the cpu while it decodes audio (which I have never heard)
I use "Load files to memory at the start of Playback" because a) its new and im trying it out, and b) I dont think there were any audio improvements with "Play files from memory instead of disk", so its not worth the extra wasted ram or processing you may notice cause a delay when you first start playback.