Gene On-board Amp/DAC good enough?

I just bought a pair of Hifiman HE 500's and i'm wondering if the onboard audio on my Maximus 6 Gene will be capable of powering these headphones. Any thoughts? I don't really want to buy an expensive amp. 

as far as i can understand yes. the hifiman HE-500, has 38ohm resistance, which the maximus VI Gene will handle nicely. some freind of mine has some beyerdynamic dt990, which is 250ohm and the MB drives them ok. though i would go for a dac if you want some better audio, like the mayflower o2 DAC

Nope, Its not enough power. I'm going to buy the O2

Interestingly, the front audio panel seems to be amplified whereas the back is not, I wonder why that is? Or maybe i'm just missing something here...