How to troubleshoot possible bad DIMM slot

RAM SLOT NOT WORKING ,GA-H81M-S dimm slot not working RAM SLOT NOT WORKING ,GA-H81M-S 2ND RAM SLOT NOT WORKING PROBLEM dimm slot not working As I said my issue was never solved, but during my research into ram slots not working, I found that some people had over-tightened the heatsink

dimm slot meaning First try spraying the RAM slot with electrical contact cleaner and try again Then try pushing on the 2nd RAM slot and then turn the laptop on,