Brad Campbell wrote:

Just a heads up. I'm experiencing "issues" with 2.6.9-rc1 that don't 
occur with 2.6.5.

I run a 10 disk raid-5 on 3xPromise SATA150 cards and a 2 disk raid-0 
on the on-board VIA chipset.
The 10 disks are Maxtor Maxline-II SATA drives and the raid-0 is a 
pair of WD2000JB drives with
Addonics SATA->PATA converters. 

Did you try RAID-0 with the pair of Western Digital drives on the two 
free Promise slots?  If that fails similarly, it might not be a libata 
issue.

-ryan