GRUB error 21, changing motherboard gigabyte 965pds3 -> ASUS P5B Deluxe-WiFi AP

I have reinstalled Ubuntu in the free space I have, the installation was sucesfull, but rebot returned the same result as before: GRUB error 21.

Then I have installed http://btmgr.sourceforge.net/3.7/sbminst smart boot manager, it have let me boot the partition with Windows, but when booting the partition with Ubuntu show again the GRUB error 21. And in fact I work more on Ubuntu... thus have Windows "ready" to be used is not a solution for me.

Thus Im sure now the error is not about Ubuntu, because it work OK in the LiveCD (wireles, sound, ...), I can mount, see and modify the Ubuntu partition, even I can install Ubuntu again in some free space I have (like I stated before but that will not work). The problem is all about GRUB and the error 21 that is "I dont know the device" or something like that.

I have a question about GRUB, is there a mailing list specific to ubuntu where I can redirect my questions, or I only have the devel mailing list at my hand??? http://lists.gnu.org/mailman/listinfo/grub-devel

Get a Window$ recovery boot disk, choose recovery console, at prompt type fdisk /mbr the command fixmbr does the same. Then reinstall grub

I must say first that the model of my motherboar is P5B not 95B.

I have attach some files in this 2 post http://ubuntuforums.org/showthread.php?p=3326908#post3326908 you can se there I have attach the device.map and menu.lst of the partition that contain Linux /.

Also I have attached a zip that contain info with the tools of GRUB LiveCD.

About what gnuskool say about windows recover disk of the MBR, I dont think that is the problem actually... I mean, I have installed smart boot manager (thus in the MBR) and it has let me launch Win partition without more problems that update the drivers for the motherboard (including the video of the geforce 8800). But, when launching the partition that contain Linux, it raise the same error 21.

With GParted boot disk, I have a nice menu to GRUB before launch the system in the LiveCD, here are like 4 options for launch/boot directly partition 1, 2, 3 or 4... but I have modified the rootnoverify(hd0, 1) for test 1,2,3,4,5,6 where the 1 is... with the result error 21.

Thus my actual question will be, OK, with gparted, I can add a complete list of instructions for launch "directly" from this GRUB my Linux partition... what configuration should I put there??? I mean:

title Ubuntu, kernel 2.6.20-16-generic
root (hd0,5)
kernel /boot/vmlinuz-2.6.20-16-generic root=UUID=3ff92915-8365-414f-a717-713c0b37a958 ro quiet splash
initrd /boot/initrd.img-2.6.20-16-generic
quiet
savedefault

I guess title, quiet and savedefault are not needed for this test with the GRUB menu at start of GParted LiveCD... ??? but what about groot=(hd0,5) that is my case for example...

I mean... is supposed that I can launch any partition available if I have a GRUB menu like the 1 that come with GParted, isnt???

The problem was the BIOS of the mother board... old BIOS dont support correctly GRUB... I dont know why something like a boot loader wasnt "supported".