After looking more deeply into this update, and doing some research I found following. It appears that Micron's memory chips dint run at rated 8gb/s speeds, they were somewhere between 7,5~7,8 or in rare cases even lower than that, and this update supposedly fixed that issue, besides overclocking, which wouldn't be the main issue, because I got micron memory as well and it was out of the box at 8004 mb/s or in other words 8gb+/s which is what is rated speed if we look spec sheets and box, and I was able to push it even further than that, my current memory oc is 8496 mb/s, you can see that while running afterburner or precision x in on screen display modes, how ever if you do see your memory is bellow 8gb/s or ~3480+something, remember double the rate (for those who are confused while looking at on screen displays), you should try the update, if you are like me and with micron memory. How ever if you have single bios card and you got this micron issue when u'r not getting your 8gb/s memory speed, and u'r not experienced or maybe a bit worried about updating gpu bios, and you dont much care about oc or your current memory speed doesn't affect you at any way, perhaps you shouldn't update the bios, because if b any chance you got electric outage or jump in your household you can brick your card just like that, it depends on you and how you feel.
Some gpu manufacturers like gigabyte still hasnt released any bios updates for their cards, since they claim no1 of their users have claimed to have any issues with micron's memory (that means all of their users got rated mem speeds 8gb/s+), how ever other vendors like asus, palet etc, how ever got these micron issues and have relased bios updates for their cards, so its not only evga's who got these issues, its simply a memory manufacturer fault, since micron memory is considered to be a lower end if compared to samsung's memory, which maybe be a true, because most of micron's memory have been shipped to europe, and euro users have affected with these memory speeds, most of american and australian users got samsung memory and doesnt need an gpu bios update, also they are the ones who can push mem oc near close to 9gb/s have seen some even with 9.2 gb/s (rare cases though).
I paid for my card 495 euros, which is pretty much, in my country, and I got micron memory, but i cant complain either I have my rated 8gb/s+ speeds.