A) There are two USB headers on the motherboard.
They are rectangular in shape, and Blue in color.
One is to the immediate Right of the 3 white PCI slots.
Has 4 pins across the Top row, and 5 pins across the Bottom row.
May have USB56 printed on the motherboard next to it.
The second one is at the Bottom of the motherboard, below the Intel 82801EB southbridge chip; which is to the left of the CMOS battery.
May have USB78 printed next to ithttp://www.ebay.com/itm/Asus-P5P800-MX-Socket-775-MotherBoard-NEW-865GV-/221041609289?pt=UK_Computing_LaptopMotherboards_CPUs_CA&hash=item33771b4a49
(Turn motherboard photo 90 degrees to the Left, to be as it sits in your computer case)
EACH USB header supports TWO USB ports.
A Card Reader uses ONE USB header, with it's two cables.
Front Panel USB ports, are connected to one of those blue USB headers.
This USB header you know to be bad.
If the other USB header is not being used, connect to it.
The front of your computer is the Front Panel.
The USB ports in the Front Panel, should be connected by one common cable, and it ends in a plug on connector.
No? Not feasible?
Then suggest using a USB adapter card, in an open white PCI slot,http://www.tigerdirect.com/applications/SearchTools/item-details.asp?EdpNo=5606148&CatId=511
Product details indicate it has two internal USB headers.
This way you can connect the Front Panel USB ports to it.http://usa.asus.com/Motherboards/Intel_Socket_775/P5P800MX/#download
Choose ANY O/S, and then download the manual.
Or, here is the direct link to the motherboard manual (PDF file),http://dlcdnet.asus.com/pub/ASUS/mb/socket775/P5P800-MX/e2005_P5P800-MX_V2.pdf
For additional questions please post in a Comment.