New ram and old ram won't work

[Misuki]

Hello. I have a ATC-605-UB11 with a i5 4440 processor and gtx 1060 6gb graphics card.

I bought some new ram a long time ago, maybe 6 months, and only 1 stick of it would ever work. I've been using that one new stick for a while but I recently tried to insert the second stick and it's not booting up at all now.

I have tried to single stick I've been using, and it has not worked. Tried it with my old ram and it still does not work. I've tried to make sure the area where it plugs into is clear with no dust and I've tried putting in all the ram in different slots but still nothing.

I would really like some help with this. This pc was pre built when I bought it.

 

[Dark Lord of Tech]

MIXING RAM is hit and miss even if identical.

 

[Calvin7]

Memory manufacturers don't guarantee old and new memory to work together. They guarantee memory in the form a kit is sold in.

Clearing the CMOS is a good idea when changing memory.

Recommended memory for your model:
Crucial 16GB (2 x 8GB) 240-Pin DDR3 SDRAM DDR3L 1600 (PC3L 12800) Desktop Memory Model CT2K102464BD160B
https://www.newegg.com/Product/Product.aspx?Item=9SIA1K63Z10961&Tpk=9SIA1K63Z10961