I currently have a gift card for guitar center from a warranty refund, which I have used partly to purchase my new DT990 Pro 250 Ohms (I had DT880 Pro 250ohms before, and when considering which headphones I wanted next I decided I wanted something with more bass), and also to purchase the ART HeadAMP 4. I already own a FiiO E7 but its battery isn't the best. For the purposes of this, it would be best if the amp or DAC suggested could be purchased from Guitar Center or is less than 50 dollars. My motherboard is the Z87 Extreme4 with the ALC1150 codec and an assertion that it can power headphones up to 600ohms. Would it be best for me to buy a different amp and return the HeadAmp4, or would it be best to buy a DAC and keep the amp, or any other permutation of these options? As for the type of music I listen to, it can be described as pop music, and I also like to play video games and watch movies.
Sorry if this post seems slightly disjointed, I have a splitting headache, and I really appreciate any help that can be given.