I have since went on to buy water-blocks for all 6 Titan Z cards, and I have them water-cooled.  That was crazy, a lot of trial and error getting that set up right, but now have it all running.

"Because the address randomly changed may cause some unexpected symptom or error on the system, our R&D team need to get the whole system including all devices, and then do the further check."

I guess I am now past the 'try this (BIOS)' stage, and if I wanted to get any more insights it would require sending in my system for an eval.  They don't have any ready answers or suggestions, and it appears they think testing would involve random and unexpected phenomenon, which leads me to believe I'm at the resource limit.  I'm not going to send in for testing, maybe I'm past the point of where ASRock's own ready knowledge goes.  But I'll keep my eye out for any new info that comes my way.  By the way, I tried adding the 660Ti as a 12th connected GPU, and I hit the "bF" error again, even with the 4G decoding enabled.  I also tried turning off any peripheral I could find in BIOS (USB 3.0, Audio, Lan), but to no avail.  Anyone interested, my hardware is in my signature.

Xaltar, you actually mentioned music recording in one of your earlier posts, and what is odd is that I never had any issue with removing and reinstalling my Creative Soundblaster X-Fi audio card.  Given that it was going into a PCI lane, I thought it might get muffed up with all the tinkering.  But nope, always works.  Guess my PC likes music production...!  

Hehe, glad to be of help :)

Xfast RAM is an app  I was suggesting you remove it if you have it installed. It improves performance but also gives access to the "memory hole", removing it may allow additional resources for your GPUs, I doubt it but its worth a shot, you can always install it again if it doesn't help 

So someone can help you, can you please post all the  (model numbers ) of your hardware.

Just so I am getting you, you were imagining me seeing an already existing BIOS modifiable that I would be able to disable right?  Or, were you actually thinking of me downloading the external utility and then tweaking something?

I understand now that the OS offers a user a viewing lens to the BIOS.  I guess a desirable BIOS will let everything load if you 'ask' it to properly, and a 'good' OS will be able to descriptively tell you what the issue specifically is, if there exists one, and give you possible options to rectify it.  It is also more clear to me that there is not ever really a 'GPU-limit', but rather a 'resource limit'. In my case a resource limit may effectively be limiting the # of GPUs, without actually having had an intent to do so, per-say.  It is because of this my search continues in looking to see what that resource is, and if I can negotiate with some part of the BIOS and OS to yield that additional resource.

Kind of imagine it like the Matrix, trying to negotiate with the process to free the GPU core.  Xaltar, you thus far have been both a Morpheus and an Oracle.  Thanks!... 

Looking under resources in windows 8.1 I see there is a check box to allow changing the allocation manually but it is grayed out. The resource tab will also show you conflicts, if you open up the properties of the GPU that is flagged "!" it may give you more info as to where the conflict is coming from. Back in the days of windows 95/98 these problems were a lot more common place and building systems back then often meant spending hours allocating resources to hardware that was trying to share with incompatible devices, especially with purpose built systems like studio/sound setups. I suspect that the checkbox to allow manual allocation may become available in the advent of a conflict. 

Another thing that may be useful to try is uninstalling Xfast RAM. Xfast RAM makes memory in the "memory hole" available to the system. Memory holes in the past were often used as additional resource allocation on certain devices so removing Xfast RAM may give your more resources to play with. I know there used to be an option on old socket 3-7 (486-Pentium) boards to enable/disable the 15-16mb hole for ISA expansion cards but I have not read up on the technicalities in modern boards for quite some time. May be worth a look.

Guess what happened...BSOD.  Oh well....

I don't know if they were referring to BIOS or OS as far as the address space goes, but I am going to assume they are speaking of BIOS.

So, I am now asking them if there is a setting that can be modified in BIOS which will allow the user allocate address space to a GPU.  I have no idea if that term 'address space' could mean more power, memory, or what....but I will see how they answer my question.  

You know, there seems to be a lot of people saying things like:

"Windows 7 can only support 4 GPU (then 6, then 8 GPU in other posts)....", or "upgrade to Windows 8, and you will get one more GPU recognized by the OS", or "motherboards only typically support 7-8 GPU."

But, how do people know this, it half feels like vague new territory sometimes.  

Also FYI, not only does device manager show 11 GPU (with one having a yellow triangle), but GPU-Z shows 11 GPU, just that one has an unknown BIOS.  I tried less than 10 GPU will all the cards, and the 1 will always install itself if it was the one previously unrecognized.  But as soon as I go above 10, then a new 11th takes its place, tries to install and cannot.  That feels like a 'resource issue' with Windows 7 address space, but I have no idea what that resource space consists of, or how to stretch that space further.  Anyway, I will update! 

Good luck getting that beast of a machine purring like a kitten