UPDATE: Got the new kit of RAM in
I forgot where I found the post but I did eventually find someone who discussed how picky these machines become about ram after you libreboot. The key seems to be dual rank with 8 chips per rank, or 2Rx8. The best sticks in my experience have been crucial/micron. I have had none of my samsung sticks boot at any capacity I had on hand. I had some ‘elpida’ that also worked.
Ultimately the kit I used was the CT51264BF160B which are 4gb dimms giving you 8gb (7 and some change after the intel gpu takes its cut). I believe this is the limit of the system to utilize.
I had tried a kingston 8gb stick but no dice their either.
Mixing the crucial and elpida seemed to work ok.
Some disappointing news though is that tp-smapi doesnt work with libreboot so you cant control charge levels of the battery like you could with the stock bios. Also the backlight has some issues now too but nothing you cant either live with or work around. Both of these issues are known and hopefully the next update of libreboot contains fixes for both.
I also tried out debian but just couldnt get used to the oddities so I’m back on mint but without having checked the non-free software box upon installing.