win7 64 not recognising all RAM in laptop

hi all

I've been searching the forums for a solution to this and I don't know what to do:

OS Name Microsoft Windows 7 Professional
Version 6.1.7601 Service Pack 1 Build 7601
Other OS Description Not Available
OS Manufacturer Microsoft Corporation
System Manufacturer Hewlett-Packard
System Model HP ENVY 17 Notebook PC
System Type x64-based PC
Processor Intel(R) Core(TM) i7 CPU Q 720 @ 1.60GHz, 1600 Mhz, 4 Core(s), 8 Logical Processor(s)
BIOS Version/Date Hewlett-Packard F.1D, 07/04/2011
SMBIOS Version 2.6
Windows Directory C:\Windows
System Directory C:\Windows\system32


so according to the MOBO spec, I could have 8Gb ram
I bought 2x 4GB Corsair memory
I have made sure that the memory chips are seated correctly
BIOS detects that there is 8GB of RAM installed
here is the system report on the RAM:


Installed Physical Memory (RAM) 8.00 GB
Total Physical Memory 3.93 GB
Available Physical Memory 2.22 GB


basically my system is detecting but not using one of the RAM chips
I don't have a setting in BIOS to map memory
I can't get to the motherboard to adjust any jumper/ voltage settings
CPU-Z shows both chips installed and working
I am running windows 64bit
been into MSCONFIG and maximum memory is unchecked

..and this is where all my efforts have now run out. so I don't get it. 8Gb installed, 4Gb available ? what do you think - dodgy RAM chip?

any ideas?


Paul

Hi all

just a thought. the windows system diagnostic is msinfo32
it lives in the System32 folder
so - if it's a 32 bit app, won't it only detect a maximum usable memory of 4Gb?

Paul.

You can also press the Windows key and the pause/break key to get to the system screen. Under system type you can confirm its a 64-bit version of windows 7 and right above that it will list your installed RAM.
A better option may be to launch the resource monitor > start menu > All programs > accessories, and have alook under the Memory tab for detailed info.