My server is a G4/733 running 10.3.9 server
It has a 2940U2W card and a Hitachi 10K disc.
Has worked fine for years.

I wanted to upgrade, so bought an Atto UL4S and Maxtor Atlas disc.

The new setup seemed to work fine on my test machine - another G4/733.

But when transferred to the server, I can't copy more than a couple of
hundred meg without the drive freezing.

Both machines have the same, up to date, Atto driver.

All combinations work fine on the test machine,
On the server:
New drive (Atlas) works fine with old card (2940U2W)
Old drive (Hitachi) works fine with new card (UL4S)

Basically, every combination of card, machine and drive works, except
the one I really want to use.

I tried 2 different cables with the same results. Bought a new one,
with the same results again.

I would say that the card and the drive don't like each other, but they
seem to work in the test machine.

So I guess the question is, what is different between the test and
production machines?

Test machine is a fresh install of 10.3.9 client
Production machine is 10.3.9 server, old install, and I wonder if I may
have messed up an extension.

But I don't really know what I am looking for....... any clues please?