If your computer has 4 gigabytes of random access memory installed, then the system memory is reported in the system information dialog box in windows vista report less memory then you expect. If the system information dialog box may report 3120 megabytes of system memory on a computer that has 4 GB of memory installed (4096 MB). If you want to access the system information dialog box, then do it in this way.
At first click on the start button, open search box and type system in the search box and then click system under programs. Now double click on the system in control panel and now click start, right click computer and then click properties. Finally click show more details in the windows vista welcome center window. Windows Vista can change to the way components of the user interface report memory.
Cause of these problems
These problems basically arise because of the address space, which is limited to 4GB in a 32-bit hardware environment. You can relocate the memory to make room for address, in this way the basic input/output system reserves for hardware. Windows Vista cannot access memory which is relocates above the 4GB boundary because of this limitation.
In the available system the reduction is depends on the devices which are installed in the computer. If you want to avid potential driver compatibility issues, the 32 –bit versions of windows vista limit the total available memory to 3.12GB. If you installed may devices in your computer then the available memory reduced to 3 GB or less.
More information about this issue
If the computer is in physical address extension (PAE) mode and has a 4GB of RAM, then a 32-bit operation system can address memory which is relocated above the 4 GB boundary. From the operating system you may know about the correct reports of the installed memory.
If you want to add more memory to the system, then the BIOS might be recognize all the physical RAM even though windows recognize only a part of the RAM. If your computer uses the redundant memory feature or a memory mirroring feature, then the full component of memory may be invisible to windows. If a memory bank fails then redundant memory provides the system with a failover memory bank. If you want to enable or disable these features then use BIOS technique, but you cannot enable or disable these features by using windows. You can modify these features with the computer’s user manual or to the BIOS manufacturer’s website.
If you want to add 4 GB of additional memory and in your computer already has 4 GB of RAM installed, then the Windows recognize only 4 or 6 GB of RAM instead of the full 8 GB.
For this problems of the memory issue (system installed with 4GB of memory), so many companies are shipping their systems configuration with 3GB total in the system
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