Hello,

I've just bought a new RAM extension of 2 GB (DDR2 667 GHz), I installed it in the last free RAM slot of my asus motrher board, but it doesn't work!!
I checked it with the system BIOS, and I could see taht the memory upgrade was recognised by the BIOS and the total extended memory become 5 GB from 3 GB but... inside Ubuntu (Jaunty 9.04) the RAM extension do not work and remained with the same old value of 3 GB.

Anyone could help me in find the way to make my Ubuntu recognizing the System memory upgrade?

thank you in advance for your help

Maiden ´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´´ ´´´´´´ a

You need to run a HIGHMEM64G kernel to get above 3GB of RAM access in a 32-bit machine.

Strictly speaking, that's "above 4GB of RAM" - various factors determine how close to 4G you actually get. I see variations from 3.4 to 3.8 Gig.
But yes, I agree that to have any chance of seeing the 5 Gig, you'll need HIGHMEM64G - my (32-bit) Jaunty doesn't have that set.

do you mean I have to install another kernel different from mine 2.6.28-12-generic one?
if yes wich one do I need to install?

ubuntu 9.04
kernel: 2.6.28-12-generic
gnome 2.26
CPU Intel dual core
GPU Nvidia Geforce 9500 gt

Thank to your answers, I was perfectly able to solve my issue:

If you're running on a jaunty 9.04 OS,
...with more then 3.0 Gb RAM...

the best and veryfied way to let yor System able to recognize and use RAM memory* upper then 3.0 gib, is to change the kernel:
It's enought that you install the same kernel version are you using at the moment but making attention to install the server version of it.
Intalling the server version of your kernel, you are enabling the "HIGHMEM64" option on your system, wich will catch the remaining part of your "lost" memory


Bye

Up the IRONS!!


*this test is made with a ddr2 RAM with a 667 mhz of BUS soeed)

Be aware hat the server kernel will be "optimized" for server funtionality, not desktop.
I haven't compared the two, and with the CFS may not be the issue it once was - but it may not be as responsive for things like video.