Question I have 2 Sticks or RAM and they both work individually but not together

[AnAngryCloud]

So I had to take apart my PC last night and everything was working at 100%. When I put it back together only one of my 8GB sticks of RAM works at a time I have reset my BIOS to default and enabled my XMS in the BIOS but still nothing I have tried with multiple sticks or RAM of two brands. When I plug in both sticks my GPU fans stop spinning after about 5 - 10 seconds and than the PC itself turns off not long after. I have tried all 4 of my RAM ports and sometimes they work sometimes they don't. Also the sticks don't work sometimes like if I plug stick A into all 4 slots in my motherboard they work I'll plug stick B into all 4 they will all work, I'll put both of them in where I usually put them and then my PC won't even stay on for more than 10 seconds let alone have anything display. I know I may have repeated myself but I just wanted to let you all know everything I have done to try to narrow down the issue my PC is working at 100% right now as I'm typing this its only when I try to use 2 sticks is when the issues start to show up. Also my Specs are below


Operating System
Windows 10 Home 64-bit
CPU
Intel Core i5 6500 @ 3.20GHz
Skylake 14nm Technology
RAM
8.00GB Single-Channel Unknown @ 1065MHz (15-15-15-36)
Motherboard
Gigabyte Technology Co. Ltd. H170-Gaming 3 (U3E1)
Graphics
ED273 A (1920x1080@144Hz)
4096MB ATI AMD Radeon R9 380 Series (Sapphire/PCPartner)
Storage
931GB TOSHIBA DT01ACA100
931GB Western Digital WDC WD10EZEX-08WN4A0

 

[RememberThe5th]

Try reseating the CPU itself.