AHCI problem

[Matthew Dillon]

:	Hi,
:
:	I switched my BIOS (Asus M4A78L-M) to use AHCI and ran under AHCI
:but I've had to switch back to NATA because after a day or two of light use
:I start getting an endless stream of these messages in the log
:filling /var (1GB) rapidly, there's no sign of trouble using NATA.
:
:Aug 26 14:36:53 df1 kernel: ahci0.0: Transient Errors: 40<PCS>
:Aug 26 14:36:53 df1 kernel: ahci0.0: Failing all commands
:
:	So far the only way I've found to stop it is to reboot, after which
:all is fine for a day or two. What is this most likely to be and how can I
:find out more ?
:
:-- 
:Steve O'Hara-Smith                          |   Directable Mirror Arrays

    PCS is a port-change signal, it would not be signaling that unless
    there was a problem with the PHY or connector.  Do you have a
    loose connection somewhere?  It is also possible to get it if
    the hard drive power cycles.

					-Matt