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

[PaulineP]

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!!

 

[Megahertz07]

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"?

 

[PaulineP]

Win 7 64-bit does not recognize 8 mb of RAM installed

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

 

[Megahertz07]

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

 

[PaulineP]

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

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?

 

[Megahertz07]

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.

 

[PaulineP]

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?

 

[Megahertz07]

If I understood, any memory stick if installed on slot B without any on slot A the laptop doesn't boot.
If so, the problem is on slot B, not on the memory sticks.
Buy a contact cleaner and spray it on slot B and on the contacts of the memory sticks. Use a cotton cloth to gently clean the contacts (memory and slots).

 

[PaulineP]

Thank you I will give it a try.

 

[7point5]

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

acetone evaporates quickly so no danger to the board

 

[Megahertz07]

Don't think acetone is a good idea. It can melt the plastic.

 

[mrjimphelps]

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

Try checking this box. The way it is worded, it sounds like you have chosen the option not to allow the maximum amount of memory. That could explain why slot B isn't working.

Also, are you getting any error code? If a memory error is detected, NUM LOCK, CAPS LOCK, and SCROLL LOCK will all flash together:

• If the pattern is OFF-FLASH-OFF, then you have a memory compatibility error.
• If the pattern is ON-FLASH-ON, then you have some other memory error.

In either case, you could have bad memory or a bad system board. But I think you have eliminated the possibility of bad memory, because each of your memory sticks works in slot A. By removing and reinserting the memory sticks in each slot, you have scraped and rubbed the contacts, thereby cleaning them. So they are probably clean enough to make sufficient contact. So if there is a hardware issue, it has to be the system board (in other words, it is likely that slot B is bad).

Here is the Service Manual for your laptop:
http://downloads.dell.com/manuals/all-products/esuprt_laptop/esuprt_latitude_laptop/latitude-e6410_service%20manual_en-us.pdf

Search through it for "LED Error Codes".

 

[PaulineP]

Ok, will do. Thanks.

 

[Mellon Head]

DO NOT USE ACETONE ON A CIRCUIT BOARD!!

Acetone will not only etch the circuit board coating off of it, but can also harm the plastic parts of the memory connector.

 

[PaulineP]

The contact cleaner did not help - system still only recognizes 4 gb installed instead of 8 (two 4 gb).

 

[Mellon Head]

It sounds as if slot B itself is bad. Is the laptop still under warranty? If so, I would advise having it serviced by Dell. This is not something that you can fix yourself.