I'm not an expert by any means when it comes to OpenBSD,

AHCI, or SATA, but here are some shots in the dark.
Does your machine have four SATA ports on it?  Can you

identify which of the four ports your two SATA drives are

plugged into?  Can you add additional SATA drives and see

if these errors are resolved or multiplied?
First guess is that the AHCI method for deciding which ports

have SATA devices attached is not working properly on your

motherboard/chipset.  Second guess is that the chipset or

motherboard has some problems with DMA happening the way

that the ahci device expects it to work.
Are there any sd devices listed after the scsibus0 line?
something like this?
scsibus1 at umass0: 2 targets, initiator 0

sd0 at scsibus1 targ 1 lun 0:  SCSI0 0/direct removable

sd0: drive offline

sd1 at scsibus1 targ 1 lun 1:  SCSI0 0/direct removable

sd1: drive offline

sd2 at scsibus1 targ 1 lun 2:  SCSI0 0/direct removable

sd2: drive offline

sd3 at scsibus1 targ 1 lun 3:  SCSI0 0/direct removable

sd3: drive offline
Kristian Rooke Wrote

quoted text
> Thanks for the suggestions.

>

> I checked the BIOS configuration and it appears that the SATA

> controller was

> set to IDE (not sure how that happened). I have now set it to AHCI, but

> I am

> seeing another error in dmesg....

>

> ahci0 at pci0 dev 14 function 0 "NVIDIA MCP73 AHCI" rev 0xa2: irq 11,

> AHCI

> 1.1

> ahci0: failed to start command DMA on port 0, disabling

> ahci0: failed to start command DMA on port 2, disabling

> scsibus0 at ahci0: 32 targets, initiator 32

>

> Does this mean that AHCI on my m/b is not supported in OpenBSD?

> Any other thoughts?