Hello, first post hai this is me and all that, pleasure to be here :) 
So I recently got a (used) 1080 Classy as a friend for my 1080 SC. The Classy is in the first slot (mobo is a x16 => 2x8 PCIE situation) and in pretty much everything appears and works as the primary card. Hardware monitor lists it first, everything is cool. But within Precision X the SC is listed up top and the Classy second. This by itself is no issue, but whenever I, say, go to OC scan the SC, it's the Classy that's pulling 100% of the load. No SLI unless I force it in nVidia control panel, btw. 
I thought the issue was that the Classy was on the second BIOS but swapping it to primary did nothing. (I found so much conflicting info regarding what those are even FOR, are they for SLI? for backup in case of brick? do they have different settings? Every source has people saying a different thing, and my card came naked as the day it was assembled, no info with it. The "manual" up on EVGA's site doesn't address it either. I can tell they have different fan curves but beyond that?) 
Now my problem with this right now is that one of this machine's primary uses is a game that doesn't play nice with SLI, unfortunately. So because card number 2 is sitting idle in it, overall temps are lower and I want to OC the Classy in a separate profile for the game only to give it a boost. Now if I go to OC scan on the Classy the card is doing its thing, 100% use and max power immediately, while the OC test window lists data on the *wrong card*, gleefully claiming the card it's testing is at 30C and 5% power. 
Can someone please enlighten me as to how Precision X determines what card is the primary and how to properly OC test on an SLI situation, specifically with different card models? Most uses I want the SLI for, and the temps as they are leave me reluctant to OC. But for single-GPU apps the Classy could definitely use a boost...