title: Flashing the ThinkPad R400 x-toc-enable: true ...

Initial flashing instructions for R400.

This guide is for those who want osboot on their ThinkPad R400 while they still have the original Lenovo BIOS present. This guide can also be followed (adapted) if you brick your R400, to know how to recover.

Before following this section, please make sure to setup your osboot ROM properly first. Although ROM images are provided pre-built in osboot, there are some modifications that you need to make to the one you chose before flashing. (instructions referenced later in this guide)

Serial port {#serial_port}

EHCI debug might not be needed. It has been reported that the docking station for this laptop has a serial port, so it might be possible to use that instead.

A note about CPUs

ThinkWiki has a list of CPUs for this system. The Core 2 Duo P8400 and P8600 are believed to work in osboot. The Core 2 Duo T9600 was confirmed to work, so the T9400 probably also works. The Core 2 Duo T5870/5670 and Celeron M 575/585 are untested!

Quad-core CPUs

Incompatible. Do not use.

A note about GPUs

Some models have an Intel GPU, while others have both an ATI and an Intel GPU; this is referred to as "Dual Graphics" (previously "switchable graphics"). In the BIOS setup program for lenovobios, you can specify that the system will use one or the other (but not both).

osboot is known to work on systems with only the Intel GPU, using native graphics initialization. On systems with switchable graphics, the Intel GPU is used and the ATI GPU is disabled, so native graphics initialization works all the same.

CPU paste required

See #paste.

Flash chip size {#flashchips}

Use this to find out:

flashrom -p internal

MAC address {#macaddress}

Refer to mac_address.md.

External flashing

Refer to spi.md as a guide for external re-flashing.

Disassembly

Remove all screws:\ \ Remove the HDD and optical drive:\ \ Remove the hinge screws:\

Remove the palm rest and keyboard:\

Remove these screws, and then remove the bezel:\

Remove the speaker screws, but don't remove the speakers yet (just set them loose):\

Remove these screws, and then remove the metal plate:\

Remove the antennas from the wifi card, and then start unrouting them:\

Disconnect the LCD cable from the motherboard:\

Remove the hinge screws, and then remove the LCD panel:\

Remove this:\

Remove this long cable (there are 3 connections):\

Disconnect the speaker cable, and remove the speakers:\

Remove the heatsink screws, remove the fan and then remove the heatsink/fan:\

Remove the NVRAM battery:\

Remove this screw:\

Disconnect the AC jack:\

Remove this screw and then remove what is under it:\

Remove this:\

Lift the motherboard (which is still inside the cage) from the side on the right, removing it completely:\

Remove all screws, marking each hole so that you know where to re-insert them. You should place the screws in a layout corresponding to the order that they were in before removal:

Remove the motherboard from the cage, and the SPI flash chip will be next to the memory slots:\

Now, you should be ready to install osboot.

Read this article to learn how you may flash the chip, which is near to the RAM.

Thermal paste (IMPORTANT)

Because part of this procedure involved removing the heatsink, you will need to apply new paste. Arctic MX-4 is ok. You will also need isopropyl alcohol and an anti-static cloth to clean with.

When re-installing the heatsink, you must first clean off all old paste with the alcohol/cloth. Then apply new paste. Arctic MX-4 is also much better than the default paste used on these systems.

NOTE: the photo above is for illustration purposes only, and does not show how to properly apply the thermal paste. Other guides online detail the proper application procedure.

Memory

In DDR3 machines with Cantiga (GM45/GS45/PM45), northbridge requires sticks that will work as PC3-8500 (faster PC3/PC3L sticks can work as PC3-8500). Non-matching pairs may not work. Single module (meaning, one of the slots will be empty) will currently only work in slot 0.

NOTE: according to users reports, non matching pairs (e.g. 1+2 GiB) might work in some cases.

Make sure that the RAM you buy is the 2Rx8 configuration when buying 4GiB sticks (In other words: maximum of 2GiB per rank, 2 ranks per card).

This page might be useful for RAM compatibility info (note: coreboot raminit is different, so this page might be BS)

The following photo shows 8GiB (2x4GiB) of RAM installed:\