TeeBoner :
Okay, so this should be a reasonably easy question, my motherboard's (ASUS Crosshair V Formula-Z) on board audio card/chip has an optical audio option. I recently saw a fairly good amplifier that supports 5.1 and optical, and I would like to use it for my pc setup. My question is, since I never saw the option in my audio manager, does my audio chip's optical SPDIF support true 5.1? So that I can play games in 5.1 using only one amplifier using the optical audio from my pc
No it does not.
S/PDIF supports the following formats:
Single channel PCM (Mono)
Dual channel PCM (Stereo)
Compressed bitstreams up to 48Khz/16bps using AC3 (Dolby Digital) or DTS encoding mechanisms.
Surround audio across S/PSIF can only be achieved using AC3/DTS. Multichannel PCM (most desirable) is not possible over S/PDIF but is possible over HDMI.
If you wish to use your external amplifier to play games that do not have native support for AC3 (almost none on PC do as it's typically unnecessary) then you must have a soundcard that supports Dolby Digital Live or DTS Connect, and an external receiver which supports decoding either one.