JonD
I know this is too late, but the other way to go would have been to spend approx. $40 for a TI chipset PCIe FW card.  (If I understand your post correctly, you bought a PCIe card, but it was a VIA chipset?).

 
Focusrite recommended a SIIG card with a TI chipset that has been the most successful; however, they went on to say that the card did have issues with some Z170 boards. 
 

Wookiee
I am running Windows 10 Home premium and using all 32Gig of installed RAM
 
My Focusrite Pro 40 works fine, but then I have PCI TI chip-set card installed.
 
The MoB is ASUS Z97-P 

I doubt TI driver will work with a VIA card different chip sets.

What breed of Z170 board are you using?

I know I saw somewhere the only the Pro version of Windows supports more than 16GB, but perhaps that Windows 7? At any rate, doesn't matter now, as I've already purchased and installed Windows 10 Pro.  Oh well. That's what I get for being impatient!
 
I'm now running the ASUS Z170-AR board.

There were a number of limitations with the variants of windows pre 10.  The main limitation these days is how much your MoB's bios supports, mine is at its limit.

See below for Windows 10 RAM limits
Windows 10 Home 32 bit 4 GBs
Windows 10 Home 64 bit 128 GBs
Windows 10 Pro 32 bit 4 GBs
Windows 10 Pro 64 bit 512 GBs
Windows 10 Enterprise/Education 32 bit 4 GBs
Windows 10 Enterprise/Education 64 bit 512 GBs

streckfus

JonD
I know this is too late, but the other way to go would have been to spend approx. $40 for a TI chipset PCIe FW card.  (If I understand your post correctly, you bought a PCIe card, but it was a VIA chipset?).

Focusrite recommended a SIIG card with a TI chipset that has been the most successful; however, they went on to say that the card did have issues with some Z170 boards. 
 

Wookiee
I am running Windows 10 Home premium and using all 32Gig of installed RAM
 
My Focusrite Pro 40 works fine, but then I have PCI TI chip-set card installed.
 
The MoB is ASUS Z97-P 

I doubt TI driver will work with a VIA card different chip sets.

What breed of Z170 board are you using?

I know I saw somewhere the only the Pro version of Windows supports more than 16GB, but perhaps that Windows 7? At any rate, doesn't matter now, as I've already purchased and installed Windows 10 Pro.  Oh well. That's what I get for being impatient!
 
I'm now running the ASUS Z170-AR board.

No, all 32Gb of RAM on my Win 7 system is available

Well, when I did a fresh install of Windows 7 Home Premium on the new setup (32GB RAM), it recognized 32GB being installed but that only 16GB was available. Ran the task manager, and it showed a total of 16GB of RAM available.
 
So perhaps there was something I needed to do manually instead of just expecting Windows to recognize it, but also there's this:
 
http://answers.microsoft.com/en-us/windows/forum/windows_7-hardware/windows-7-is-it-32-or-64-bit-and-how-much-ram-will/ba73a9b1-142d-4a90-860c-db19a325327d?auth=1
 
But again, it doesn't really matter at this point, as I have already purchased and installed the new hardware and OS. (And for what it's worth, I did chat with a rep at Microsoft and she also stated that in order to utilize 32GB of RAM in Windows 10, I'd need the Pro version, so apparently she was confused as well.)

The specs for ASUS Z170-AR says it will support 64gigs of Ram

Just a thought are all your RAM modules the same?

Wookiee
The specs for ASUS Z170-AR says it will support 64gigs of Ram

Just a thought are all your RAM modules the same?

To just clarify, I'm no longer having any issues now that I've built a new PC and installed a new OS. On my current setup (which includes the Z170-AR), everything is working properly and Windows 10 is recognizing all 32GB of RAM I have installed.
 
Previous discussions were based around my attempt to put Windows 7 Home Premium on my new setup, and with that OS, it wasn't recognizing everything. Plus several other things didn't really work either (it was a shot in the dark anyway) which is why I ended up getting Windows 10 and doing a fresh install from the ground up.