Still can't get 4GB

Friday, November 11th, 2005

My new IDE disk drive (PATA, that is) arrived from Newegg today. I stuck that baby in there and disabled SATA in the bios. Fedora got to “Welcome to Fedora Core” and then froze. Twice. Ubuntu froze at “Creating initial device nodes”. When it freezes, the computer’s keyboard doesn’t respond to capslock or numlock. Nor does it respond to ctrl-alt-del. A poke at the reset button is required. Another try with Ubuntu got to the point of trying to install the SELinux package before it locked up.

Bill recommended I try backing off the memory and see if I got the same problem with just 1GB of RAM instead of 4GB. I yanked the RAM and gave Ubuntu another shot…. it got much further and is still going! It says it is 50% done with the install of the base system now. Go Ubuntu! I suppose now is when I should start googling for boot parameters for large memory linux systems…

Core system installed successfully and now it is installing remaining packages. Cool.

Hmm, according to this, it doesn’t sound like modern machines need to have the amount of RAM specified at boot. The machine passed the BIOS RAM test at boot with 4GB, but there was that note in the motherboard manual that said something about only 3.4 GB being visible.

The Ubuntu install finished smoothly. Amazingly smooth. I’ve never seen such a smooth Linux install. But then, I’m usually installing on crappy old, hand-me-down computers. I can’t wait to try out the SATA drives as soon as I get this memory thing nailed down.

Oh, and for the record: 3981 bogomips out of the AMD 64 Dual core 3800. But it doesn’t register as two CPUs… I thought it would show up just like a hyperthreaded CPU does. I guess I have to make sure SMP is active…

The snazzy package manager for Ubuntu made it easy for me to find and install the SMP kernel for AMD. Now my bogomips show up as 3981 for CPU0 and 4014 for CPU1. Sweet.

OK, time to see how much memory I can add before it freaks out. The working config I have now is with just 1GB.

Booting with 1GB, the bios registers the memory as single channel.
Booting with 2GB, the bios registers the memory as dual channel.
Booting with 3GB, the bios registers the memory as single channel.

But those all seem to work. Well, at least I don’t see the random lockups that I saw with 4GB.

This poor fellow describes my symptoms pretty well and comes up with the conclusion that the problem is the motherboard. He has a Asus A8N SLI Premium (Board revision 1.2, Bios revision 1011, nForce4 A3) motherboard. I have an MSI K8N Neo4-F. Checking the many reviews of my board on newegg.com shows that other people have had problems getting the board to use more than 2GB even though it is advertised as being capable of 4GB.

On an MSI-hosted forum, I found this answer to the problem of 4GB ram being seen as only 3GB:

For anyone who has this problem, u need to enter the BIOS, select

Cell Menu -> DRAM configuration

Then enable

H/W Memory Hole Remapping &
S/W Memory Hole Remapping

Bada bing, all sorted

There is also this thread at an AMD-hosted forum on the same problem.

Tuesday, January 10th, 2006

I tried again to get my AMD64 3800 in an MSI K8N Neo 4-F motherboard to recognize more than 2GB. After all, the board says that it supports up to 4GB and I have these 4 sticks of 1GB RAM from Corsair sitting here…

I tried loading the RAM, adjusting the BIOS to enable memory hole remapping and then booted into Ubutu Breezy Badger. It never made it through the process of starting services. I tried a few times and it would either reboot or lock up at different places while starting services.

I went back into BIOS and tried nudging up the memory voltage. I only went up one notch to 2.70 (I think… I didn’t make a note of the value). The bios gave a set of green values, yellow values, and red values. I selected the highest yellow value.

Same problem.

At this point, I took out 2GB and gave up for the night. But at this point when I tried to reboot, I couldn’t get X to start. It gave me Sig 11 errors. Ugh. I fiddled with temporary files, and permissions and eventually got nuclear and removed all the xserver-xorg packages and reinstalled them.

That got me back on track. It was even smart about saving my tweaked xorg.conf file so my closed-source nvidia driver still worked.

But back to the drawing board for getting the board to accept 4GB.