For $140 (I know its over your budget) You can get the Ultrasone Pro 550. I got mine last night and so far it has been great. Great for gaming, great for music, great for blue-ray movies, and decent bass.
It doesn't have Dr Dre. beats bass, but it definitely has bass. I'm sure you can make it sound real good with proper equalizer settings. I am a hip-hop guy so bass is very important for me and so far I'm pretty satisfied with these all-around headphones and how they seem to be good for everything.
Amazon.com: Ultrasone PRO 550 S-Logic Surround Sound Professional Headphones: Electronics
Edit: I am also a very big PC gamer. Not disappointed as far as gaming goes.
Edit #2: They come in silver, not blue.
Edit #3: My soundcard is shipping tomorrow so all of this is the difference I heard with on-board. Meaning the bass with proper EQ settings + soundcard might be much better then my 1st impression of it.
I second this suggestion for the Pro 550s. Ultrasone designs them to have adequate soundstage (but really good for a closed headphone), and they have phenomenal bass response. They are quickly overtaking the ATH-M50s (which have recently experienced a price hike due to popularity) as the most commonly reccomended closed headphone here.
They are a really a 'do-it-all' headphone, suited to mostly any genre, and still able to game with somewhat accurate positional audio cues.