Hi. Nearly 3 weeks ago I disconnected the usb keyboard. (it was at the back) then I connected to the front but sometimes it doesn't work. I get a message "power surge on hub port. A usb device has exceded the power.....". What can I do to solve this problem. it doesn't matter if I connected to the front or the back.
Not sure if this 100% correct, but I was told once that the rear USB ports are direct from the board, and any others are 'additions', and as such do not carry the same power ratio. Bit like USB1-USB2 I suppose?.
Each USB port is capable of supplying 500ma current. The ones on the backplane are connected directly to the motherboard. The ones on the front are usually connected by means of a cable to headers on the motherboard so in effect are also connected to the motherboard. Power problems usually arise when connecting an unpowered hub to a port as the power available on each hub port is divided by the number of ports e.g. a 4 port hub has 125ma available on each port.
The problem in this thread would appear to be associated with the amount of power being drawn from a port exceeds the 500ma max and its just a guess but this could be due to an electrical short in either the keyboard, its cable, or the plug or a fault in the keyboard electrics.
The problem basically started when I removed the keyboard without using the "SAFELY REMOVE HARDWARE" option. Not only I'm having problems with the keyboard but the mouse too when I removed it and change position. A year ago I have a similar problem with a NEW external hard drive. Can someone give some light about the importance of using the "SAFELY REMOVE HARDWARE". Thanks