How to DIY-repair fried USB ports on Mac mini?

Hi, try this first...

reset FW bus, same goes for USB reset...

Reset the Firewire bus

If your Firewire or USB isn't recognizing any device. A solution which has worked for some whose hard drive became invisible in 10.4 was simply to follow these four steps to reset the Firewire/USB bus:

1. Shut the machine down.

2. UNPLUG the power lead to the computer and any firewire/USB drive or devices.

3. leave it for 10 minutes.

4. Connect back up and reboot.

http://www.macmaps.com/firewirebug2.html

Try one USB device at a time.

I don't have access to schematics for your model but as far as USB you may be into the logic board. Perhaps you can find a Firewire 800 device that has USB outputs to work around the fried portions of the mini.

Were all Peripherals, cables, & power sorces removed when you did this?

DIY soldering repairs are pretty much out of the question.

Most, if not all, IC's that would be related to the problem

are of the BGA (ball grid array) variety and require special

equipment to remove and replace as all the connections

are under the IC.

The only DIY alternative would be to purchase a logic board

and replace it yourself. Just Google "mac mini logic board

replacement" for sources and how to's. Apple themselves,

will not sell you logic boards, so you need to get it from a

third party vendor. As to which ones are are the most reputable,

I cannot really say. I would suggest avoiding any Ebay offers

that are not reputable retailers.

As usual, be aware that if a price on such an item is too

good to be true, it probably isn't.