Sound card necessary with headphones?

So I have Sennheiser HD580's about $150-200 headphones, they sound great but am I going to REALLY notice a major difference with a X-Fi or something like it versus my onboard sound on my Asus Rampage board?

I play a lot of games, listen to a decent amount of music and I do enjoy good sound but is it worth the $85 to upgrade without a speaker system?

Thanks in advance for all opinions

Mobo audio has VERY poor analog outputs in general. The signal to noise ratio and gains are really not up to par with such outstanding headphones. The above choices still use the analog outputs from the Mobo header audio output. So garbage in, garbage out.

You got two choices. Get a premium soundcard with great analog (mini rca jack output/headphones) and the power to push them like they need to be.

Or use the digital output off the Mobo sound card and connect it to something (I have no idea) that has the right quality outputs for headphones.

I use my optical digital out and pump it to my amp/speakers, so my speaker amp gets a pure signal, and IT has the good stuff to give me clean sound. Your awesome headphones deserve the same. Get a great soundcard or a headphone interphase that has digital input.

Bower, I have the Senn HD595's, so I'll know you've got a good set of cans. The best thing you can do for them is get a dedicated headphone amp. I currently use a Firestone Spitfire DAC with a Cute Beyond headphone amp ( http://www.firestone-audio.com/ ), and I've use the affordable and good sounding HeadRoom Total Bithead ( http://www.headphone.com/products/ [...] ithead.php ).

A headphone amp will do way more for your headphones than any soundcard can and the difference is clear. Dynamic range is totally opened up and you'll get to hear much more accurate bass. The Total BitHead has a USB input too so, no soundcard is even necessary, but you can plug in your favorite MP3 player as well.

You've got good headphones. A little headphone amp will let you hear how good they can sound.