Just received my RMA today, here is what I know so far:
IMPORTANT! EVGA Precision XOC does not fully remove itself after uninstalling/reboot - I had to delete registry settings in order to clear out my existing profile and allow entry of new Serial #.
* Card does not appear visually to be any different from the existing - maybe a little darker color on the heat-sink.
* After DDU, re-install drivers, and XOC boosts to 2025Mhz/5005Mhz on default profile.
* Running 8 hours of Heaven Bench before anything else, and so far no problems after an hour with temps 50-60c (MUCH cooler than before).
* ZERO COIL WHINE.
* EVGA Customer Support FTW!! (groan).
Fingers crossed.
NOTE: I have never had any coil whine with the past 3 cards (MSI GTX 760, MSI GTX 970, EVGA GTX 1080 FTW) on this MOBO/PS (Old Gigabyte p67+Thermaltake 850W modular). However my old MSI GTX 970 sings like a bird in the machine I built for my Nephew which is a newer ASUS Z97ar/i5-6700K/1000W - go figure.
EDIT: 'Chips' on the back are 65 lot, my existing card actually had 66 lot.
UPDATE 1: It is clear this card is clocking down at much lower temps than my previous one - 1960Mhz@60c whereas my existing card would hit 2020Mhz@75c. That is not a complaint just an observation - it is still astonishingly fast.