Really Forte better than stx but specification tells something else.It's S/N is less,frequency response and is it support Windows 7?
If your main focus is gaming the Forte is the better card and it also features a dedicated headphone amp and is Windows 7 ready.
I have one cost me $130 taxes included.
The STX is no different then the Xense for gaming it still uses software.
Don't take my word for it though it's your money.
I'm sure the Asus is well over $100 more.
I'd use the extra money for better speakers or headphones.