Windows 7 64-bit does not recognize 8 GB memory installed

Hi,
I have installed two (4 gb) chips of memory on my Win 7 Pro 64-bit laptop but the system (BIOS/Computer Properties/Task Manager-Performance) - only recognize 4 gb. The memory chips snapped in the slots perfectly. If I remove one, the system recognizes 4 gb. If I load one of the chips in either slot, the system recognizes the 4 gb but as soon as I load both 4 gb chips, the system does not recognize 8 gb as it should but still only recognizes 4 gb. I made sure the BIOS setting for maximum memory was unchecked. I updated the drivers. I rebooted the laptop but it still only recognizes 4 gb Any suggestions?? Thanks!!

Welcome to the Forum.

Are the two (4 gb) chips same brand and model?
Are the two chips recognized on BIOS?
What you mean by "I made sure the BIOS setting for maximum memory was unchecked"?

Yes, the 2 chips are of the same brand: Crucial DDR3L-1600 SODIMM 1.35V CL11

No, I do not believe the 2 chips are recognized in BIOS:

BIOS/SYSTEM INFORMATION/MEMORY INFORMATION:

Memory Installed: 4096 MB

DIM Size A – 4096 MB

DIM Size B – DIM slot empty

The maximum memory box in the BIOS/Boot/Advanced Options is unchecked

Take the main battery off, remove Dim A leaving on only Dim B and see if it is recognized on BIOS.

The BIOS did not recognize Dim B. I removed one of the 4 gb from DIM A leaving only DIM B loaded and the system would not even boot. When I had a 4 gb in DIM A and another in DIM B the system recognized the 4 gb in DIM A only. When I only loaded one of the 4 gb in DIM A, again the BIOS recognized the 4 gb in DIM A. Suggestions?

Put memory from DIM B (that isn't recognized) on DIM A to see if it's the slot B or the memory stick that has the problem.

If I install the memory that was in slot A into B, the laptop will not even boot up. Only if I have either memory stick in slot A will the laptop boot up and when it does, only 4gb are recognized. I am not sure how the slot itself could have a problem but it is starting to look that way or maybe there is some internal setting I am missing?

Thank you I will give it a try.

if all fails try cleaning inside the slot with some acetone (using a q tip)

acetone evaporates quickly so no danger to the board