ultra 133 controler downgrades to PI0 mode why?

[John Wheez]

Hi,

I have two new Promise TX2 Ultra 133 ATA controllersin my alpha 164lx. Each
controller has one 250 gig ATA133 maxtor drive attached to it.

My boot log as an entry such as:
ad1: 239372MB <Maxtor 7Y250P0> [486344/16/63] at ata3-master UDMA133
ad1: UDMA ICRC error cmd=read fsbn 0 of 0-3 retrying falling back to PI0 
mode.

Both cards get this same message...I have a new antec power supply in 
the case as well
and new ATA 133 cables which came with the promise cards....

Is there any way I can get these controllers working at ATA 133?? ideas 
suggestions always welcome :)

John