Cant decide on headphones for mainly gaming

[joeyhiggins112]

I've decided to ditch these crappy uncomfortable Logitech G933's for a new Headphone & mic Setup.

I can't decide on what headphones though. So far I've assorted this list below.

-Sennheiser HD 598SR OR Beyerdynamic DT 990 PRO (Can't decide)
-Blue Microphones Yeti USB Microphone - (I'm happy with it.)
-FiiO - E10K Olympus USB DAC and Headphone Amplifier (if necessary)
-ASUS Xonar DG PCI 5.1 Audio Card (if necessary)

The main thing after reading a bit is that if i go with the DT990's i'm gonna need to get an Dac/Amp to truly enjoy the DT990's & a sound card if i wanna play on 5.1 which is my preference.

Although I'm really not sure if i need to buy the amp & sound card with my motherboard,
any advice on these specific points would be greatly appreciated.

Thank you.

Here's my build:

 

[Lutfij]

Both the headsets are stereo and require a stereo source so there isn't going to be any true 5.1 audio outputted to the cans. The sound card will come in handy if you have a speaker system that is 5.1. If not then my suggestion is that you refrain from the amp's/DAC's and work off the Realtek audio chip. If you think there's more to it, then you can invest in a quality sound card or a USB driven DAC.