Is it harmful for the laptop (the mainboard) if you have 6 different devices connected to a USB HUB (without power supply) that draw current permanently?
If it were harmful, would the problem be solved with a USB HUB with a power connection?
No.
No, there are no problems with it, as long as all components get enough juice, that's good. If you use high-end components that draw a lot of current, I would recommend one with an additional power supply, so that components do not go off every now and then
It's not harmful, no. The mainboard supplies a certain amount of electricity and if that is not enough, yes, then it is just not enough and the connected devices may no longer work as they should.
Yes, if that's the case, a USB hub with an external power connection should fix the problem.
