Question PC Won't Boot After Installing New Ram

[ScrawnyYT]

i have this problem for about almost these entire pandemic but still can't fix it. I search the internet that the old ram must not be together but i installed the new ram only and it didn't turn on. First I thought the ram was broken but I went to the shop and changed it... it still the same problem.

 

[SM/Madao]

-is it Laptop or Desktop?
-if is a Desktop, what Model of the MOBO(same goes to Laptop Model)
-And also RAM Model.

Preferred to just told us full spec if that possible.