Buying headphones + amp for gaming and music (electronic)

Hello, I've never owned headphones before, and I have very little experience using them.

I am aware that the ones I have used before (don't remember the brand/model) made my jaw hurt, so comfort is my primary concern. If I don't like how it feels, I'm not going to want to wear it, and there's no point having it.

I work from my computer so I expect to be wearing them for 8 hours or more every day on a regular basis.

With my free time I will be using them for gaming and listening to music (mostly electronic... Pretty well everything except dubstep).

For gaming I mostly play starcraft, but also sprinkle in some FPS like BF3 for variety. I wouldn't call myself super competitive, but it does rub me the wrong way and affects my enjoyment of the experience when my peripherals feel limited or don't respond properly.

I'm looking for an open design, as I need to be able to hear my surroundings (someone at the door, kettle boiling, phone ringing, etc). As much as I'd love to, I can't just block out the world for 8+ hours a day :P

My current set up is a $15 pair of Sony earbuds plugged into my keyboard, so pretty much anything will be miles ahead of what I have.

I figure this is an investment that I will get plenty of use out of, so I'm willing to spend up to the $500 area if it's really going to make the difference between "good enough" and "I love it!" (that's about as much as I can really afford).

Preferably I would rather spend closer to $200-$300 if I can get away with it.

The Beyerdynamic DT770's seem like a good possibility with great reviews and solid opinions on both their comfort and performance.

I've also heard some good things about the Sennheiser PC360, but I'm a little taken back by some claims that the bass is a bit lacking. The microphone is nice, and an improvement over what I'm using now, but it isn't essential at all.

I haven't really looked into amplifiers too much. I've noticed some people here recommending Mixamp. I don't really understand amplifiers too much though and wouldn't specifically know what I'm looking for yet without some further reading.

Since I'm new to the world of headphones, should I maybe look at buying used instead?

Can anyone point me in a solid direction or recommend some good setups that fit my needs and budget?

Thanks. :D

Thanks, I should maybe mention that portability is not a priority at all. :)

Any opinions regarding comfort on the DT 990 Vs. the DT 770, or are they the same in that respect?

Thanks, you guys are awesome!
 

Ok so I'm a little confused...

If I were to get the Fiio E10, I would have the headphones plugged into the amp, and the amp would go into the computer through USB...

Or, I could invest in a soundcard with a headphone amp in it and plug the headphones directly into that...

So what's the difference between one and the other?

It seems like the Fiio E10 has more driving power for higher quality headphones, while the soundcard in the same price range gives you bells and whistles (dolby), and enough driving power for more 'consumer quality' headphones.

It's amazing, I've been building computers for years, and I'm just now realizing that I know very little about audio equipment or soundcards, and I've been finding it rather difficult to find a good rundown of all the technical terms and a good explanation of all the equipment and what really goes into a good system. If anyone can point me to some good articles for beginners. I've found lots of articles about the components individually, but nothing that really explains how they all work together to produce the finished result.

Haha, you've just thrown a whole new component into the mix with AV receivers...

It's funny, I had no idea this morning that the dry skin and irritation in my ear from the earbuds would have me spending the whole day scouring the internet to break into the world of audio equipment.

It's a little overwhelming to be honest, this must be how non-computer people feel when buying a computer. Of course I know from experience that this is just an initial learning curve I need to get over, and things have, and will, start to connect until I can take all these great suggestions base an informed decision from them.