No worries and that's awesome you're digging them. I picked up an iFi Zen Dac Signature and Zen Can for my desktop use. The Zen Dac (non-signature version) is a dac/headphone amp and you get a lot of awesomeness for the money. My bet is you'd definitely hear a difference when it comes to music but not so sure about positional audio in gaming - although my guess is that if you're not doing any audio processing DAC wise right now, you'd see a boost in positioning and detail of that with a DAC.
There are a few gaming centric DACs too: Schiit Hel, Sennheiser has one, and there was another that is escaping my memory. ;)
High end motherboards have pretty sophisticated audio systems, mine features a 10 channel DAC.
My Asus Dark Hero:
ROG SupremeFX audio technology delivers an exceptional 113 dB signal-to-noise ratio on the line-in connection to provide best-ever recording quality. There's also a low-dropout regulator for cleaner power delivery to the SupremeFX S1220 codec, an ESS® ES9023P digital-to-analog converter for superior front-panel output, and a Texas Instruments® RC4580 op amp for high gain with low distortion — all to produce unmatched audio quality.