Kubuntu shows 3 GB RAM when installed 4GB

[medalex]

Hello,
I have recently installed Kubuntu on Toshiba P300 and noticed that it shows total memory 3 GB of RAM, but actually it is 4. May be you know how can I check the physically installed RAM memory? Can it be the hardware problem (for example one memory is broken os smth else)?
Looking forward to your ansewers.

[arochester]

Re: Kubuntu shows 3 GB RAM when installed 4GB

Have a look at "Detected 3960mb of memory instead of 4096mb" on http://kubuntuforums.net/forums/inde...opic=3102644.0

[medalex]

Re: Kubuntu shows 3 GB RAM when installed 4GB

Thank you for reply, but it seems I have another problem.
Here is the free:
total used free shared buffers cached
Mem: 3092296 2981572 110724 0 25832 540204
-/+ buffers/cache: 2415536 676760
Swap: 10000420 11756 9988664
As I can see total memory is 3092296. It seems that 1 GB is missing.
Can ypu advise some software for testing memory?

[musta ruhtinas]

Re: Kubuntu shows 3 GB RAM when installed 4GB

Which version of Kubuntu have you installed? Is it the 32bit or 64bit?
My guess it's that you installed the 32bit version, and then this is perfectly normal.
You can either install the 64bit version or compile a custom kernel to support this amount of memory.

[dibl]

Re: Kubuntu shows 3 GB RAM when installed 4GB

Make sure that the 4GB shows in BIOS -- the BIOS has to recognize it before the OS will recognize it.

Only the 64-bit OS will automatically pick up memory above 3GB, unless you compile a special kernel as musta has said.

[medalex]

Re: Kubuntu shows 3 GB RAM when installed 4GB

It seems that you are right.
lsb-release:
DISTRIB_ID=Ubuntu
DISTRIB_RELEASE=9.04
DISTRIB_CODENAME=jaunty
DISTRIB_DESCRIPTION="Ubuntu 9.04"

and uname -a gives
Linux alex-laptop 2.6.28-11-generic #42-Ubuntu SMP Fri Apr 17 01:57:59 UTC 2009 i686 GNU/Linux

I have Intel(R) Core(TM)2 Duo CPU P8700 @ 2.53GHz processor. Can I install 64 bit version of Kubuntu with it or I must recompile a kernel? Where can I read about kernel and how it must be recompiled to work correctly with 4 GB of RAM?
Thanks.

[dibl]

Re: Kubuntu shows 3 GB RAM when installed 4GB

YES, you can simply install the standard 64-bit Kubuntu, and all your memory will be used automatically. I personally use the Alternate Install CD -- but the Live CD will work just fine. The main difference is that there are more KDE packages on the Alternate Install CD, since it does not need to show the GUI desktop environment.

Fair warning -- it is a very rare day that your system will actually use 4GB of memory. Mostly it will be used for disk cache, which is fine, but not for running processes. So don't expect to observe a dramatic performance difference during normal use of the computer.

[medalex]

Re: Kubuntu shows 3 GB RAM when installed 4GB

Thank you very much, I have reinstalled my Kubuntu to 64bit version and now it shows about 4GB of RAM.