Defective Ram Slot
Missing RAM: Windows might show that you have less RAM than you actually have seated. This can usually be solved by re-seating the RAM or switching the slots the RAM sits in, but if not, this could indicate that you need a replacement stick. If you see the RAM modules are ok but the problem is with your RAM slot, Then you will need to contact with computer manufacture customer support. If your warranty is expired, Go to an expert technician who can help you. In that case, You may need to replace your motherboard. Sometimes, Reconnecting RAM modules can fix the problem.
This guide will require installing and removing DIMMs from motherboard to specific DIMM slots.
1. Please insure that the system is turned off while removing memory. Remove all but one DIMM of RAM.
2. Single DIMM should start in DIMM_A1.
3. Start system up and confirm that the system posts to BIOS/OS.
4. If the system posts normally, shut off system and continue to install one additional DIMM until the system fails to post to BIOS/OS.
How To Fix Defective Ram Slot
When installing DIMM should hear/feel a click when DIMMs are installed correctly.
Faulty Ram Slot
Use the following Guide for optimal memory configuration depending on how many DIMMs system has.
Faulty Ram Slot
5. If the system fails to post remove last DIMM installed and set aside, continue from last DIMM slot and install another stick. (repeat with any other failed DIMMs)
Defective Ram Symptoms
6. If multiple sticks fail in the same DIMM slot install a confirmed working DIMM and verify if the slot is bad. (Make note of defective slot using DIMM guide DIMM_D1, etc.)