USB ports on 2009 27" iMac dying... what can I do?

[iindigo]

It would seem that the USB ports on my 2009 quad 2.66 i5 27" iMac are dying. External drives plugged into them only show up in Disk Utility for a split second, forcing me to plug them into a hub. This forces them to mount, but the connection intermittently dies and comes back to life before the disks dismount, causing missing disk errors in applications and causing my keyboard and mouse to miss keystrokes and clicks.

I'm running Mountain Lion final. This is definitely a hardware issue; booting into a different OS doesn't help.

What can I do, short of paying for a several-hundred-dollar motherboard replacement? I never bought AppleCare and had the motherboard replaced once during its original 1-year warranty.

 

[Fishrrman]

Could it be a "loose cable" issue at the "port end" (iMac's USB ports)?

Do you get any alerts or error messages when the drives "dismount"?

Even if the drives disappear in Disk Utility, do they still mount using just the finder?

Have you tried changing cables?

I'm thinking one of the "contact points" on the iMac's internal USB port might be loose or dirty.

If you open System Profiler, and click on "USB" (on the left), what does it say on the right?

"What can I do, short of paying for a several-hundred-dollar motherboard replacement?"
If push comes to shove, are there "firewire-to-USB" adapters that might work in place of the non-functional USB ports?

Some I found - although I have no idea if they really work:
http://www.ebay.com/sch/i.html?_nkw=firewire+to+usb+adapter

 

[robgendreau]

You could put those drives in FW enclosures and use bluetooth for the keyboard and mouse. Cost wouldn't be as high as replacing motherboard, which just doesn't seem cost effective.

If you are at all handy, there are articles out there on how to attach an external esata port to the internal sata for the DVD drive. But that means sacrificing it. And that wouldn't help with other USB peripherals. Or buy an iMac with a dead screen or something and replace the logic board. Again, doesn't seem super cost effective. But again, since it's failing, maybe worth a try. There's a teardown of that year's imac at ifixit:

http://www.ifixit.com/Teardown/iMac-Intel-27-Inch-Teardown/1236/1