I had a problem initializing and partitioning a new Seagate Barracuda 400GB drive with the NexStar GX (NST-370GX) external USB enclosure. Neither my G4 MacBook Pro or my Mac Mini Dual core could initialize or partition the enclosure/drive. I could however hook the enclosure up to my XP machine, format it using NTFS, and access (read) the drive on my Mac Mini just fine. I didn't check it on the laptop though after formatting it using XP. This still was unacceptable.
After doing some searching online, I discovered this post on 123macmini.com:
where the post points out that the NexStar GX enclosure is a rebranded Macpower M9-LX. Then I discovered on the Macpower site:
that the enclosure is not compatible with any Seagate Barracuda drive greater than 160GB. Doh!
After swapping out the Barracuda drive for a 300GB Western Digital drive I could then initialize, partition, and use the enclosure on my Mac Mini without any problem.
I was using OSX 10.4.7
I hope this helps others out there with the same configuration.