[nutellarise]

I'm looking for a first pair of headphones, and I picked the beyerdynamic dt770s because most reviews said they are super comfy for under ~150, which is very important to me.
 
I dont really understand the difference between the 250, 80, and 32 ohm ones. I will be mostly just plugging it into my PC without an amp, will I have trouble with the headphones?
 
Also - If you know where i can find some good deals that would be great!