Hope this will help you I have used a software from Passmark
My sound card is not that powerful as yours at the following example below in picture it is currently outputting 128 KHz at 24 bit stereo sound 300 Hz sinewave. You can change stuff in here to check for your requirements.
192 KHz may show up in your card
My sound card only supports 128 KHz sampling rate maximum
To check this go to Settings -> View wave capabilities - Windows
Select I/O -> Output
Device -> Select the device you wanted
In "Format sound card driver clams to support" scroll to the bottom you get the most powerful output options here is mine example.
As Mitch said best way to check is using a oscilloscope but that's something belongs to https://electronics.stackexchange.com ...
You can also try the vb-audio software too