You certainly don't want to turn off 5.1/7.1 output, if game has output channel configuration settings.
If game outputs only 2.0/stereo most spatial data is lost forever.
Anyway if your thinking buying one unless there's some 2/3rds off discount, GSXes are gaming trinket overpriced for having cheap phone/tablet level D/A converter and equally weak output.
They're basically low end as DAC and headphone amplifier is equally BS.
Budget/entry level 30-40£ Audigy Fx/Xonar DGX actually have better DAC.
Cheaper than GSX priced Sound BlasterX G5 has couple classes superior DAC and headphone output.
SBX G6 adds Dolby Digital decoding for full usability with consoles.