Plugging iPhone 5 into computer resets USB hub and devices
Wow, 7 USB ports is a lot for a laptop!

Because (as you mentioned) the iPhone and iPad consume above-standard amperages, they can sometimes cause issues such as this.  Most USB controllers are dynamic enough to simply provide a standard amount of power to just the iPhone, but there have been a couple of cases I've seen where the hub crashes as you're describing.  When the hub provides a USB-standard amperage to the device, the device will indicate that it is not charging (though explicitly indicating that it is plugged in).

I'm interested to know what model laptop you're using as it may be a known issue for the corresponding USB controller.

As for a fix, you can see if there is updated firmware for the controller.  If those are unavailable or don't resolve the issue, I suggest getting a powered external USB hub.  Using one will eliminate the power strain on the motherboard and will probably extend the life of the PSU.