I have an asus a555lf with x555lf mother board. itcame with 4 gb ram, and a free slot. i bought another stick of 4 gb ram and installed it. but it doesnot get detected. i have tried updating the bios but it doesnt work. please help.
Are you running a 32 bit version of Windows or a 64 bit version?
32 bit can only use 4GB of memory.
Does the memory show in BIOS?
There seems to be a lot of confusion in the industry about what's commonly called the Windows “4GB memory limit.” When talking about performance tuning and server sizing, people are quick to mention the fact that an application on a 32-bit Windows system can only access 4GB of memory. But what exactly does this mean?
By definition, a 32-bit processor uses 32 bits to refer to the location of each byte of memory. 2^32 = 4.2 billion, which means a memory address that's 32 bits long can only refer to 4.2 billion unique locations (i.e. 4 GB).
In the 32-bit Windows world, each application has its own “virtual” 4GB memory space. (This means that each application functions as if it has a flat 4GB of memory, and the system's memory manager keeps track of memory mapping, which applications are using which memory, page file management, and so on.)
This 4GB space is evenly divided into two parts, with 2GB dedicated for kernel usage, and 2GB left for application usage. Each application gets its own 2GB, but all applications have to share the same 2GB kernel space.
SOURCE: http://www.brianmadden.com/blogs/bri...ally-mean.aspx
Check the BIOS first. If that doesn't report 8 GB, then the OS won't ever see it, even if the OS is x64.
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