|Flashing the bios is NOT a fix-all !|
You may have noticed that you are often told NOT to flash your bios unless you must, where bios updates are listed on the mboard model's downloads page, and often also in the mboard manual.
NEVER update your bios version, unless you find specific info for a bios update, (or for bios updates newer than the one on your mboard but older than the one you're flashing with, since the newer bios updates usually include all previous fixes), e.g. release notes on the same page where the bios updates are, that specifically says it will fix a problem you are having, or unless you need to update the bios to support a CPU your present bios does not support.
Flashing the bios is the riskiest thing you can do with a mboard ! The relatively primitive bios flash chip can only be flashed a small number of times, and the flash chip can even physically fail the FIRST time you attempt to flash the bios !
If the flash chip physically fails, your mboard cannot boot the next you attempt to boot after flashing, and forever after. The bios chip must be replaced with another one that has already been flashed beforehand. On most mboards these days, the bios chip is soldered into the mboard rather than being in a socket. The soldered in bios chip can be replaced by specialists, but you have to ship the mboard to them, wait for it to be shipped back, and it is often cheaper to buy a new mboard instead !
Those directions I quoted were for a Silicon Image chipset EIDE PCI card with RAID capability. Since SATA controllers became available, EIDE controllers are sometimes called PATA controllers.
Look at the manual for your Asus mboard model.
If you do not a drive controller card in a mboard slot, you have two drive controllers that have RAID capability built into the mboard.
One may be for an EIDE RAID capable drive controller, the other for a SATA RAID capable drive controller,
...or you may have two SATA RAID capable drive controllers and the main chipset EIDE controller has no RAID capabilty (in the latter case you would probably have more than 4 SATA headers available).
If a drive controller, EIDE or SATA, has RAID capability, it loads it's own line early in the boot sequence, and you can access the RAID utility for it at that point if you wish, within, say, 5 seconds - by pressing a stated key - if you don't press the stated key, the boot sequence continues.
You can't make a RAID array unless at least two hard drives are connected to the same RAID capable drive controller.
You DO NOT have to set up a RAID array for any RAID capable drive controller, but the option is there if you want to do that. If it's a SATA RAID capable drive controller, it's also capable of running SATA drives in SATA non-RAID mode.
(By the way, when you load SATA drivers, if you are given the option of either the drivers for a certain chipset without RAID support, and drivers for the same chipset WITH RAID support, if the chipset IS capable of RAID, load the drivers for the RAID capable chipset even if you don't want to use a RAID array - in my experience, the non RAID drivers will NOT work for a RAID capable chipset.)
"No device detected, Utility disabled!"
That indicates there is no hard drive connected to that Silicon Image RAID capable drive controller. In that case, it does NOT load the capability to load the RAID utility, because there is no need to.
The message is normal for that situation - you can ignore it.
E.g. if the Silicon Image RAID capable controller is EIDE and you have no EIDE hard drives connected to it, of course, no suitable hard drives will be found connected to it.
"The other is the MediaShield utility (F10 at startup). I can access this one,....."
That indicates there is at least one hard drive connected to that RAID capable drive controller.
" ....but the option to make a new array is grayed out. I can delete the existing array,...."
My guess is there's nothing wrong with that situation - it's grayed out because it's grayed out when an existing RAID array is detected.
"I can delete the existing array, but I don't want to do that until I'm sure it won't result in data loss."
As I have said, I don't know much about RAID arrays.
You need to do more research.
The directions I quoted don't directly describe what to do about your situation, but it seems the Rebuild procedure for when you have a RAID 1 array does not delete the operating system's data on the drive that's still okay.
Did you look in the Asus manual for your mboard to see what info it has about setting up a RAID array etc. ?
Did you look on the Asus web site for RAID info ?
"Outlander: All SATA ports are enabled in BIOS, as is nVidia RAID function. Is there anything else I should adjust in BIOS?"
You shouldn't need to adjust anything.
If the bios having the SATA controllers set to SATA mode worked fine before, Windows obviously has the drivers for the SATA controllers installed in the operating system. It sounds like you ARE able to access the first drive, but not the second one, I would guess because the metadata has the wrong drive connection info when the drives are connected to SATA 3 and 4.