A Bit of background that may or may not be directly related with the issue :
My laptop broke around a month ago, with the power supply of the mainboard being the issue. Now it's all well and fine
So i was requiring an extra ram for my laptop due to it often running out of RAM (slowing down, etc) and i use many demanding programs on my computer. So after consulting with a friend about the ram, i bought a 4GB DDR3 PC-12800 1600GHz V-GEN ram, which should be compatible with my laptop's ram. When i first installed the ram, i succesfully booted on to windows and i noticed that my extra 4GB of ram went to system reserve instead of working ram. so i toyed with some settings from msconfig, to no avail.
Then i went to System and browsed advanced system settings, and i changed this :
to use custom size and set the max size to 8GB. i forget the default value of this so im scared to change it back
as for msconfig i went to this part :
and set the maximum memory to 8gb, also to no avail..
and suddenly it wont ever boot whenever there is a ram on the second slot.
both ram works, it will not work if a ram is installed on the second slot, no matter in what combinations possible from 2 rams and 2 slots.
I tried cleaning the ram slot with a brush as i do not have an isoprophyl alcohol with me, and since the slot is not reachable with a pencil eraser.
Could this be an issue with the ram slot being dirty, or an aftermath of an unfinished repair on the mainboard psu?
Laptop : Lenovo z50-75 80ec
OS : WIndows 8.1 64-bit