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Wickd
January 18th, 2009, 08:51 PM
Hi there

I have installed Ubuntu Intrepid on my work laptop (HP 6530p). I then discovered that it only detects about 2.9GB of my total of 4.0GB primary memory?

Can Ubuntu only detect 3 GB of Mem?

Thanks

jfr1tz
January 18th, 2009, 08:55 PM
in 32bit mode yes, 64bit can use the full 4gb.

bbzzdd
January 18th, 2009, 08:56 PM
32-bit operating systems can only address 4GB of RAM. Depending on your install/motherboard, that extra 1GB is to other things like memory mapping, etc.

Install the 64-bit version to see all 4GB.

blothian
January 18th, 2009, 09:05 PM
Hello, if you have 4gb, 32 bit will only detect 3gb but will still use the 4gb, but 64 bit will show all 4gb.
Hope this helps
Benjamin.

Wickd
January 19th, 2009, 10:41 AM
So it will still be able to use the full 4GB, but wont see all 4?

Thanks! For some reason I cant give you a thank you on the forum...

Cheers

jespdj
January 19th, 2009, 02:36 PM
This is a frequently asked question.

If you're running a 32-bit operating system (Ubuntu, Windows, or whatever else), you will at most be able to use 4 GB minus an amount reserved for communicating with I/O devices and your video card.

If you're using a 64-bit operating system, you will most likely be able to use more of the 4 GB. Look if your BIOS has a "memory remapping" setting. This will move the addresses reserved for devices out of the way so that a 64-bit OS can use (almost) the whole 4 GB.

My laptop running 64-bit Ubuntu can see about 3.9 of the 4 GB.

If you have more than 4 GB, you'll need a 64-bit OS (or a 32-bit OS with PAE (http://en.wikipedia.org/wiki/Physical_Address_Extension) enabled, such as 32-bit Ubuntu Server).