Ubuntu 12.10 on AMD64 missing microcode boot error

No Plymouth and Module Load Error:

I don’t get the fancy Plymouth screen at boot, and I get this annoying message;
“failed to load file amd-ucode/microcode_amd.bin”

AMD 64bit Quadcore CPU Microcode Module:

So, first to get this error fixed, then Plymouth later. As i’m using a 64bit AMD Quadcore CPU, I guessed it was a module either failing to load or a non-existent module, and a bit of Googling proved me right.

**Note
In the comments Mathias pointed out that you can install the needed module from the Ubuntu repos, whereas below I provide a step by step manual install. To install it automatically:

sudo apt-get update && sudo apt-get install amd64-microcode

I downloaded and installed the microcode manually from AMD:

http://www.amd64.org/support/microcode.html

First download and add the AMD public key to your keyring and verify the signature:

To import the key (when downloaded from amd64.org) use
gpg –import ucode.sign.pgp.pub

To download the public key from keyserver use
gpg –keyserver keys.gnupg.net –recv-keys 9F94BC90

The key fingerprint is
0719 2E77 C9C5 79D6 D122 6AC3 6257 68B9 9F94 BC90

To verify the integrity of the GPG key fingerprint use
gpg –fingerprint ucode@amd64.org

To verify the integrity of the container file package use
gpg –verify amd-ucode-latest.tar.asc amd-ucode-latest.tar

Now let’s download this module and get it installed, locked and loaded:

1. Create a directory for the module:

sudo mkdir /lib/firmware/amd-ucode

2. Go here and accept the conditions to download the tar file: 

http://www.amd64.org/index.php?id=50&file=amd-ucode-latest.tar

3. Extract it.

cd Downloads
tar xf amd-ucode-latest.tar
cd amd-ucode-2012-09-10

4. Copy the microcode over to the firmware directory:

cp microcode_amd.bin   /lib/firmware/amd-ucode
cp microcode_amd_fam15h.bin    /lib/firmware/amd-ucode

5. Now remove any old modules, and reload your new microcode module:

sudo modprobe -r microcode

sudo modprobe microcode

That’s it, now reboot and you should be blessed with an error-free boot