How JustAnswer Works:
  • Ask an Expert
    Experts are full of valuable knowledge and are ready to help with any question. Credentials confirmed by a Fortune 500 verification firm.
  • Get a Professional Answer
    Via email, text message, or notification as you wait on our site. Ask follow up questions if you need to.
  • 100% Satisfaction Guarantee
    Rate the answer you receive.
Ask Pat Your Own Question
Pat, Mac Enthusiast
Category: Mac
Satisfied Customers: 171
Experience:  10 years of systems administration experience in mixed Mac and Windows environments
Type Your Mac Question Here...
Pat is online now
A new question is answered every 9 seconds

I have a mac pro and want to add a PCI Express 5 port USB card

This answer was rated:

I have a mac pro and want to add a PCI Express 5 port USB card to it. The card requires power and has a four pin power connector. Is there a spare power connector on the power supply and how do I find it?

You've got 2 choices, the first one is probably the easiest:

Choice 1:
Power is available in the SATA drive bays where you put in extra hard drives. These are the numbered bays at the top of the case right above where the motherboard is. You'll need an adapter like this:

These might be hard to get into place, take a look at the case and see if you think you'd be able to get the power connector into place, it won't be easy.

On a related note, there is a molex power connector in the drive bay where the Superdrive is located. However, I'm not aware of an easy way to route the cable back into the rest of the case.

Choice 2:
There are power connectors on the motherboard at the top left of the board. They are black plastic. Here is a picture of them, the black cables you see in this picture are connected into the board. Its hard to see in the picture but should give you a general idea. Use a flashlight to see them:


This one requires a bit of engineering and 2 cables. You need this one:

and you need this one:

you'll have to cut one of the connectors off of the second cable and attach a 4-pin Molex Female connector onto it. Sorry that there's no easy answer, Apple should really have some Molex connectors in this part of the case, but they don't.
Pat and 2 other Mac Specialists are ready to help you
I'm not aware of a card that doesn't need a power conneciton, but its possible that this card will work without it, you just might run out of amps connecting devices that are powered by the USB bus. If you stick to connecting things that have their own power supplies (like hard drives that have an external power adapter) then the card will probably work. If you need someone to make the cable for you, let me know. I might be able to find a source and have them put it on ebay.

Edited by Pat on 2/6/2010 at 10:19 PM EST
Customer: replied 7 years ago.
Thank you, XXXXX XXXXX been very helpful.