Thanks!
Since I have never had any experience with DACs or Amps before I had no idea how a cheap amp or DAC would perform so knowing that onboard audio is probably just as good is really useful. I wasn't sure if an Amp was necessary mainly because, on one of the Techquickie videos, it recommended an Amp for headphones with an impedance of greater than 50 ohms and the OB-1 has an impedance of 54 ohms but if onboard audio is capable of driving that then that's fine.