Turning on USB HardDisk Rack Crashes Computer

[mortar]

Hi i've got a problem where I plug in any hdd into my IDEtoUSB converter and as soon as I turn it on, even before i get a chance to mount it, it scans for the device for a while, then dmesg reports errors, and re-mounts (sda3) my root partition as read-only and basically leaves the computer unresponsive as though the HDD is faulty.

I'm running the latest gentoo-sources kernel on ~amd64. The same problem occured before when I had a ~x86 installation, different motherboard, different cpu, different memory modules. I've got two different racks and they both do the same thing. Is there anything that i've left out in the kernel or compiled wrongly?

The strange thing is that plugging in a USB thumb drive works fine, has no ill effect what-so-ever. So i'm wondering whether or not it's power supply related or it does have something to do with the way gentoo is configured..

The interesting thing that I discovered just last night is that If I plug the drive in before booting the system, at boot time it's detected fine (by coldplug i'm assuming) and I can mount and unmount it till the cows come home and theres no problem. Admittedly I haven't tried to unmount and remove the USB drive while running Gentoo since last receiving the error, as i'm worried that it may be damaging my linux drive or destroying my linux installation filesystem?

I'm sorry I don't have the error on hand so I can't give you exactly what it said, but basically reported a fault on drive sda. I've tested both the linux drive and all drives that i've tried to plug into the USB Rack, all produce the same error.

Any ideas would be greatly appreciated!