I have in my possession an EVGA MoBo that in my opinion is too awesome a board to retire. The 790i.
Actually, I have a couple components. I'm wondering what would be a good way to go about things.
I currently have "shelved" my 790i(s) because I had acquired a SSD sATA PCIe Adapter ( http://www.tigerdirect.com/applications/searchtools/item-details.asp?EdpNo=4811997&SRCCODE=WEBGOOPA&cm_mmc_o=mH4CjC7BBTkwCjCV1-CjCE&gclid=CIbmuJ-y6r0CFcaCfgodBBEA1g ) for increased (C:\) performance and couldn't get it functioning right-off-the-bat, so rather than wasting time I went ahead and switched out to ASUS Z77 Sabertooth board and currently have it equipped with a 3770K + SSD w/ Tempo Adapter + ~12TB RAID (D:\) ... no RAM though (currently borrowing a friends spare RAM till I can afford to equip it myself). Anyway though, what I would ultimately like to accomplish is to have the 790i as my primary computer until something more along the lines of like an x98 chipset debuts. But I can't figure out how to get this Adapter Compatible--because the (C:\) performance is limited/restricted by its sATA II ports (and this adapter blows sATA III out of the water)

...
Here's a list of what I am working with,
EVGA 790i FTW (132-YW-E179)   [DZ19]
EVGA 790i Ultra (132-CK-NF79)    [P08]
Intel Qx9770
Intel Qx9650
... I've heard that some people were able to accomplish running 2x8GB RAM modules on the 790i board(s),, I'm sure that the different models make a difference in achieving that though. I currently have 4x1GB 1333MHz & 4x2GB 2000MHz to work with between the two, but was wanting to attempt to get 2x8GB @ 1866MHz stick running with Qx9770 @ >4.0GHz ; at least 10TB (D:\) {RAID}, with SSD+Adapter (C:\) [which I hope is do-able]
 
Between the two models, which is the better of the two? (Which one should I equip for the job[?])
Any recommendations/suggestions for what I should do is appreciated.
Thank You.
 
(EVGA 7800 GTX , 8600 GT , 9800 GTX , 250 GTS , 670 GTX & 760 GTX Video Cards)

Out of what is listed the 790i Ultra is the best

Pastulio
What necessarily makes the Ultra model the best (between the other [EVGA] 790i model boards? [Ultra / FTW / Digital PWM / ...])?
Also, does anybody have any sort of recommendation toward how I should go about getting the "Sonnet Tempo" card functioning with the 790i MoBo?     ... would(should) Flashing(updating) the BIOS be enough to fix it?    >.<

The ultra model should allow you to overclock the best of all of the models if that is what you wish to do.
 
You should try and have the BIOs of the motherboard to the latest possible version but there is no guarantee that card will work in that motherboard until you actually try it and you are using an operating system which has drivers for it.