May have a 128GB limit
I have a B&W G3, and recall reading somewhere that the stock IDE controller has a limit -- it can't handle drives bigger than 128GB. I've never confirmed this, but read it in enough places that I suspect it may be true. You might check lowendmac.com or some similar site.
I got around this problem by putting in a SIIG SATA PCI controller card ($60) and a 160GB SATA drive as my boot drive, while leaving the old 20GB IDE drive where it is.
Hope this helps.
Andrew
EDIT: oops, I see you solved your own issue. Ignore my post.