I've just downloaded a recenet ubuntu image .. I heared it runs smoothly (not entirely) from the SD card .. but I want to install it on the internal memory to get better results with the Os performance . is there a way to make it install on the internal memroy on my n900 and make a dual boot ??

Just put me in the right direction
Thx in advance

i have the same question
( how to install it on eMMC ? )

Follow NITDroid instructions but extract Ubuntu rather than Droid..
Seems easy enough.

Edit:
Link: http://wiki.maemo.org/Nitdroid_easy_install_on_EMMC

Replace Nitdroid files with ubuntu and find a right kernel.

did u manage to boot into ubuntu with the guide?

and also, do we need R&D mode?

not dual boot, but theres also this:

http://talk.maemo.org/showthread.php?t=66531

just main points :

you need linux on your pc for this

first you need to repartition the internal memory ,easiest solution is to install backup menu , and get it to load , press "w" , now all partitions on the internal memory will appear as mass storage devices on your pc , shrink MyDocs , to free some space , move other partitions to the left , so the free space is on the right , create your new partition here .

just a note : if you want to install multiple OS on the internal card , create an Extended partition , and divide the space inside it by the number of OS you want to install , creating a logical partition for each .

extract the ubuntu rootfs on your newly created partition , note that if you are using the TI image , this can't be applied directly , instead use dd to apply the image to your sdcard , and tar up the rootfs then untar it on your new partition .

now you need a working kernel , you are on your own here ,

the following assumes you want to use u-boot :

when you get your kernel , convert it to a uImage , convert the Initrd to uInitrd using mkimage .

I assume the first partition on your sd-card is a fat/fat32 partition..

you also need to write uboot script to load ubuntu .

I will assume the partition where you install ubuntu is the 5th partition on your emmc ,
1st is MyDocs
2nd is home
3rd is swap
4th is the extended partition start
5th <-your first logical partition

create a new file call it uboot.ubuntu
inside it paste the following
now convert that file to boot.scr , using mkimage
copy the boot.scr , uImage , uInitrd to the first partition of your sdcard .

you need to get a kernel that ubuntu can use to boot, and need to configure some files on the ubuntu partition correctly such as watchdog configuration amongst others, however these issues are the same as when installing on the sd-card .

I installed debian on my internal card using guide at
http://elektranox.org/n900/
and based the information written above about the uboot-part on what's written there at
http://elektranox.org/n900/kernel/uboot.html
I just made small changes so It can boot from the internal card .

Can you specify how you setup watchdog? Setting it up according to elektranox.org site my N900 reboots after a minute, I can't get the watchdog config right. Your help would be greatly appreciated.