These are my current specs:
Case: NZXT Phantom 410 - White
CPU: Intel Core i7 OC'd at 4.1ghz
GPU's: Two GTX 670's in SLi
RAM: 8GB's DDR3 1333mhz ADATA Gaming series
Mobo: Z68 Asrock Extreme 4 Gen 3
CPU Cooler: Corsair Air Series A50 CPU Cooler
PSU: OCZ 850w Gold Certified
SSD: Crucial M4 256gb
HDD: 2TB thingiemajig
Steelseries 7H Headset
Steelseries Sensei Raw Mouse
Steelseries Qck Microfibre Mousepad
Logitech 5.1 Surround Sound System
Would a Xonar Essense STX make much difference to sound quality on my 7H's and Logitech surround sound system and do I have a beefy enough PSU to accomodate one?