When I look at the PS for my D-Ling 7 port it's claims to be 2.5 amps. That's why they run 5 miners. The Rosewill 520 10 port well run 8 miners. I'm working on converting a atx psu for a 30+ amp 5 volt supply.
you put to much through you could fry the hub...
No, not at all. The amount of available current has nothing to do with it. A hub well only take the amount of current the asic's require. My 10 port Rosewill hubs run 10 miners, powered by the 5v rail of a atx psu, rated at +5v/36Amp. I've seen some cheap import hubs that can't supply 0.5 amps per port because of a cheap surface mount fuse that blows, 10 ports needs a minimum of a 5 amp fuse yet some cheap 10 port hubs have 3-4 amp fuses.
There's a thread someplace that shows how to change these surface mount fuses, fairly simple but you need good soldering skills.
ask anyone whos amped up the amps through a cheap ass hub theres loads of picture the components simply cant take it and most melt from there being to much current going through them. usb hubs take what they need but the cheap ones dont realise there components cant take it heat up and blow or belt. im not saying this always happens as it varys from hub to hub but im just saying theres a risk and it CAN prove to be a fire hazard..