I think a major challenge here is all the different setting and options available. Some ease-of-use enhancements to the BIOS would be nice (a SATA-x option in the boot order options would be a great start.) Seems to me they just keep adding on more and more to existing BIOS rather than start fresh, but I the economics probably dictate this.
In any event, let me describe what I have and what I know does and doesn't work for me.
First, I have an 81K1100 - this board only has 2 SATA ports and 2 IDE controllers (all from the ICH5.) The SATA ports can be setup as RAID0 or RAID1 - again an ICH5 feature - but turning this on requires you to use a custom boot device driver in WinXP.
I'm now running a BETA BIOS revision F7a, however I don't notice any feature difference between this and the released F6 BIOS in the area of disk controller setup.
There are several features here that all interact. Besides the standard settings for configuring the IDE controllers, we have the setup of the SATA ports. They can be configured to be just straight SATA or can be setup to mimic an IDE controller and port. Doing so prevents that controller from being used - if you have SATA-0 setup as IDE Primary Master you can't use the Primary IDE controller at all (even the slave port.) You can set this mimic mode manually, or leave the SATA setting to AUTO - this will cause the BIOS to set it to mimic whatever IDE controller you don't have devices on automatically. I admit I'm not sure why this feature is needed - I can't see any reason for you to want the SATA drive to show up as IDE.
You also have the ability to turn on or off the SATA RAID support. With the support OFF, apparently the controller acts like an IDE controller (this a guess - anybody know for sure?) With the support ON, the controller is an ICH5-RAID controller and requires a customer driver for Windows to work properly (in RAID configuration, you can't see the controller in Windows without the driver, and you need that driver to boot off this controller.) This is the same behavior you'd get if you used a high-end RAID controller like an HP SmartArray in your system.
Another BIOS features controls the boot order. You get to set the order the system uses to try to boot the system - on this mobo you have the option to set 3 things it should look through and the order to do so. Seems simple enough, except that the list of options here is huge - each IDE hard disk port is available (HDD-0 through HDD-3), there are 5 options for different USB devices, boot to LAN, ZIP drives, and the ubiquitous CDROM and floppy. Whew! Oh, and another setting marked simply SCSI. This is an interesting one because selecting this one doesn't in fact specify exactly which SCSI controller to boot from (after all you could have several SCSI controllers.) Instead, there is another BIOS setting marked 'RAID/SCSI boot controller' that allows you to specify which over your various SCSI/RAID controllers should be booted when you select SCSI in the boor order setting. It is this setting that you must configure correctly when you want to boot off of the ICH5's SATA RAID controller. This is not obvious - especially if you have IDE drives in the same system.
OK, so given this lengthy discussion of features, here is what I believe does and does not work with the current BIOS on the 81K1100. I have 2 IDE HD (both on the Primary controller), 2 IDE CD-ROMs (both on the secondary controllers), 1 Adaptec Ultra SCSI controller with 1 drive, and 1 SATA drive. Because I only have 1 SATA drive I'm disabling SATA RAID and have no intention of using it.
I would like to boot from the SATA drive (being the fastest, I'd like to use it for the OS.) This is not possible at the moment due to a BIOS bug with my configuration.
With all the devices in the system and the BIOS settings set correctly (that is boot order set to SCSI, and SCSI/RAID controller order set to SATA) the system insists on booting from the Adaptec controller.
I then removed the Adaptec controller (I can get the data off it from another system and live without it really.) That leaves me with 2 IDE HD, 2 IDE CD-ROMs, and the SATA drive.
Unfortunately, the system still won't boot from the SATA drive. The SCSI/RAID controller order setting won't even show that you have a SATA controller in this mode (which ultimately probably shows the real bug.) No boot order setting will allow you to boot from the SATA drive.
I then disabled my IDE HD - this then allowed the system to boot from the SATA drive. Great - but I'd sure like access to my disks.
I then disabled my IDE CD-ROMs, set the boot order to HDD-2 and the SATA drive to mimic IDE Secondary Master. This boots, however the Primary IDE disks are hosed - you can sort of access them but you get major drive errors and I/O problems. I'm convinced the current BIOS isn't programming I/O right.
I then moved my IDE HD to the Secondary IDE controller, set the boot order to HDD-0 and the SATA drive to mimic IDE Primary Master. This boots and I can access my IDE HD. Great! Now I'd like my CD-ROMs back .
I'm hoping that this saves somebody else some headaches and if anybody sees another option or choice I've missed I've happy to give it a try!