The bst way to check if your USB 3.0 hard disk needs a driver is to connect it to your USB 3.0 interface card while its running under Windows - you should see the new hardware wizard pop up if this is a first time connection and then it will either find a driver on the hard disk or ask for one. It might be simpler to just have a look at the software poovided by Seagate on the USB 3.0 hard disk and see if there are any drivers present. I have a Western Digital 2Tb USB 3.0 hard disk and there are drivers supplied on the disk.
When I was testing this USB 3.0 drive with my new system which has USB 3.0 ports on the motherboard, I placed both the motherboard drivers and the hard disk drivers onto a USB stick that boots WinPE (created as per this article: Adventures with WinPE Symantec Connect
Having booted WinPE from this stick, the USB 3.0 drive plugged into the USB 3.0 port was not actually accessible via WinPE. So the first step was to load the USB 3.0 interface drivers for the mobo from the WinPE command prompt:
DRVLOAD (path and filename of motherboard INF file from mobo driver dir on USB boot key))
WinPE responded with a message to confirm that the drivers had loaded.
The next step was to load the drivers for the USB 3.0 hard disk:
DRVLOAD (path and filename of USB 3.0 driver INF from hd driver dir on usb boot key)
Again, WinPE responded with a message to confirm that the drivers had loaded.
Once these two steps were completed, I was able to find the driver letter on which the USB 3.0 drive was now to be found, and was able to read and write to the drive. This process confirmed that I had the correct Vista 32 bit drivers required by my version of WinPE. To avoid having to use DRVLOAD each time, the next step would be to integrate the drivers into WinPE and create a new bootable WinPE image. This is something that the Ghost software pretty much automates for you, but you need to first add the drivers, and then select them from the list of all available drivers otherwise they will not be included in the new boot image.
One other thing I would like to mention at this point - my new system includes a 3Tb hard disk internally, and I found that under Windows 7 64 bit, the largest "regular" partition I could create was 2Tb. In order to use the full capacity of the drive as a single partition, I had to use the GUID partition option. I'm assuming that the same limitations may exist for an external USB drive that exceeds 2Tb in capacity, but what I don't know is whether a large single GUID partition can be mounted under WinPE 2.0. Perhaps not an issue today, but something to bear in mind as USB 3.0 devices grow in popularity and size.