Schiit Magni takes the cake currently, I believe. Of course a pure headphone amp depends on having a decent DAC stage, which would be the line out (not headphone out) of your motherboard.so what’s a good amp?
This may be true, but it's not something you're likely to be able to discern from spec sheets published by ASUS. If your B450 board is having trouble with 80Ohm DT770s... well, that's just weak.Although I think the both have the same audio setup.
DT770 were my number one gaming headphones until I received my Takstar GM200, which IMHO are superior all around. You may be aware of Cooler Master MH751 gaming headset. Takstar makes them but their own version (both the Pro82 studio model as well as GM200 headset model) are superior to the Cooler Master version. These 60e have no right to sound this good, for both gaming and music and this is coming from a person who's number one music cans are Hifiman He500 planars...
But digress, you will not go wrong if you get the DT770. Just make sure you get the 32 ohm version if you do not have a headphone amp. Their soundstage is good for a closed headphone, bass is strong and reaches really deep down to 20hz without any roll off and yet there is no boomy bloat to be found. It is good quality bass, even if it is clearly elevated from neutral. Treble is sparkly and has nice sense of detail, but can be fatiguing to some. Their only real weakness is that midrange is recessed, they have a clear V shape thing going on. This is why I consider my new Takstars superior because they offer pretty much everything what DT770 has but midrange is not as recessed, and are cheaper to boot.
*Edit For what its worth, my DT770 is the 250 ohm one. But there should not be massive difference between different impedance models, the basic sound signature is the same. The only odd man out would be DT770M which has even higher isolation and is made for drummers.
I've heard good things about the Takstar GM200, but is it good enough to warrant a purchase if I already have the MH751? I've read BenF's review on Head-Fi & the GM200 thread there as well, but am still not sure.