The old G3 ATA bus can't read more than 128 GB's....
If you want to exceed that limit you must get a PCI ATA-133 (or S-ATA) card.
The B&W G3 can handle Mac OS X Server 10.4.11 as max, but you'll need plenty or RAM (512 MB minimum) to get it running a bit decently.
Depends on what you want to do with it.