don't detect 4GiB memory. Help me!

[JamesLe]

I'm use laptop HP Compaq 8710w core2duo cpu 2.6GHz, Memory 4GiB
I'm just install Fedora 16 x86_x64. But it only detect 3.8Gib Memory.
What wrong at here? Please help me! Thank's so much!

[jpollard]

How much is reserved for your video? Some video interfaces take/use main memory for storage and that gets subtracted from the available memory.

Is the BIOS reserving memory? Some BIOS functions mirror parts of themselves into main memory for speed (or other purposes) and that can remove memory from the system. Usually the BIOS also includes a control to limit the amount.

Otherwise, you can use the PAE kernel instead. Since you only have 4G memory, the 64 bit use doesn't really buy you much (programs are bigger, requiring more storage than the 32bit versions).

[PabloTwo]

What does the output of this command say?
cat /proc/meminfo | grep MemTotal

[Gareth Jones]

I'm use laptop HP Compaq 8710w core2duo cpu 2.6GHz, Memory 4GiB
I'm just install Fedora 16 x86_x64. But it only detect 3.8Gib Memory.

This is pretty normal. Only memory which is available to the page cache (file caching, buffers, user-space processes) is reported by most tools. Some memory is reserved by BIOS, hardware (e.g. video and DMA devices) and by the kernel itself, and is not available for the rest of the system.

---------- Post added at 06:00 PM ---------- Previous post was at 05:56 PM ----------

cat /proc/meminfo | grep MemTotal

Redundant use of cat award. ;)

Gareth

[PabloTwo]

Yeah, I keep forgetting you can treat the files in /proc just like a regular file when it comes to grep.
BASH:~/-> grep MemTotal /proc/meminfo
MemTotal: 4031128 kB
There, happy now? :)

[JamesLe]

Thank's all friend for Reply!
I'll check my System.