After installation of new SSD, Macbook Pro 15" Retina won't wake up after it goes to sleep mode My old 256GB SSD died, and I've brought a new SSD with 512GB. After installing new SSD and OS, everything works just fine. 
But now I have this issue with sleep mode: Macbook goes to sleep, it won't wake up. It will start if I hold the start button for a while. 
I tried to reset the NVRAM and SMC, it didn't resolve anything.
I'll be glad to hear any solutions from you, will try everything to get rid of this issue.

Specs:
Macbook Pro 15" Retina with Quad-core i7 2.2Ghz, 16GB.
That can happen with non-Apple SSD-sticks, even Apple ones from the wrong year's model can cause those exact symptoms. You can't take one from a 2015 MBP 15 and attempt to use it in a 2013 model, although it will work in the 2014.

You'l just have to find the right one for your exact model; Transcend's JetDrive line of SSD-sticks for Macs are well delineated on their product site.