ThinkPad T400 {#pagetop} ============= It is believed that all or most T400 laptops are compatible. See notes about [CPU compatibility](../install/t400_external.html#cpu_compatibility) for potential incompatibilities. There are two possible flash chip sizes for the T400: 4MiB (32Mbit) or 8MiB (64Mbit). This can be identified by the type of flash chip below the palmrest: 4MiB is SOIC-8, 8MiB is SOIC-16. **The T400 laptops come with the ME (and sometimes AMT in addition) before flashing libreboot. Libreboot disables and removes it by using a modified descriptor: see [gm45\_remove\_me.html](gm45_remove_me.html)** (contains notes, plus instructions) Flashing instructions can be found at [../install/\#flashrom](../install/#flashrom) [Back to previous index](./). EC update {#ecupdate} ========= It is recommended that you update to the latest EC firmware version. The [EC firmware](https://libreboot.org/faq/#firmware-ec) is separate from libreboot, so we don\'t actually provide that, but if you still have Lenovo BIOS then you can just run the Lenovo BIOS update utility, which will update both the BIOS and EC version. See: - - NOTE: this can only be done when you are using Lenovo BIOS. How to update the EC firmware while running libreboot is unknown. Libreboot only replaces the BIOS firmware, not EC. Updated EC firmware has several advantages e.g. bettery battery handling. Compatibility (without blobs) {#compatibility_noblobs} ----------------------------- ### Hardware virtualization (vt-x) {#hwvirt} The T400, when run without CPU microcode updates in coreboot, currently kernel panics if running QEMU with vt-x enabled on 2 cores for the guest. With a single core enabled for the guest, the guest panics (but the host is fine). Working around this in QEMU might be possible; if not, software virtualization should work fine (it\'s just slower). On GM45 hardware (with libreboot), make sure that the *kvm* and *kvm\_intel* kernel modules are not loaded, when using QEMU. The following errata datasheet from Intel might help with investigation: The T400 is almost identical to the X200, code-wise. See [x200.html](x200.html). Hardware register dumps {#regdumps} ----------------------- The coreboot wiki [shows](http://www.coreboot.org/Motherboard_Porting_Guide) how to collect various logs useful in porting to new boards. Following are outputs from the T400: - T400 with **Winbond W25X64** flash chip (8MiB, SOIC-16) and Lenovo BIOS 2.02 (EC firmware 1.01): - [../future/dumps/logs-t400-bios2.02-ec1.01/](../future/dumps/logs-t400-bios2.02-ec1.01/) - Version of flashrom used for the external flashing/reading logs is the one that libreboot git revision c164960 uses. Copyright © 2015 Leah Rowe <info@minifree.org>\ Permission is granted to copy, distribute and/or modify this document under the terms of the Creative Commons Attribution-ShareAlike 4.0 International license or any later version published by Creative Commons; A copy of the license can be found at [../cc-by-sa-4.0.txt](../cc-by-sa-4.0.txt) Updated versions of the license (when available) can be found at UNLESS OTHERWISE SEPARATELY UNDERTAKEN BY THE LICENSOR, TO THE EXTENT POSSIBLE, THE LICENSOR OFFERS THE LICENSED MATERIAL AS-IS AND AS-AVAILABLE, AND MAKES NO REPRESENTATIONS OR WARRANTIES OF ANY KIND CONCERNING THE LICENSED MATERIAL, WHETHER EXPRESS, IMPLIED, STATUTORY, OR OTHER. THIS INCLUDES, WITHOUT LIMITATION, WARRANTIES OF TITLE, MERCHANTABILITY, FITNESS FOR A PARTICULAR PURPOSE, NON-INFRINGEMENT, ABSENCE OF LATENT OR OTHER DEFECTS, ACCURACY, OR THE PRESENCE OR ABSENCE OF ERRORS, WHETHER OR NOT KNOWN OR DISCOVERABLE. WHERE DISCLAIMERS OF WARRANTIES ARE NOT ALLOWED IN FULL OR IN PART, THIS DISCLAIMER MAY NOT APPLY TO YOU. TO THE EXTENT POSSIBLE, IN NO EVENT WILL THE LICENSOR BE LIABLE TO YOU ON ANY LEGAL THEORY (INCLUDING, WITHOUT LIMITATION, NEGLIGENCE) OR OTHERWISE FOR ANY DIRECT, SPECIAL, INDIRECT, INCIDENTAL, CONSEQUENTIAL, PUNITIVE, EXEMPLARY, OR OTHER LOSSES, COSTS, EXPENSES, OR DAMAGES ARISING OUT OF THIS PUBLIC LICENSE OR USE OF THE LICENSED MATERIAL, EVEN IF THE LICENSOR HAS BEEN ADVISED OF THE POSSIBILITY OF SUCH LOSSES, COSTS, EXPENSES, OR DAMAGES. WHERE A LIMITATION OF LIABILITY IS NOT ALLOWED IN FULL OR IN PART, THIS LIMITATION MAY NOT APPLY TO YOU. The disclaimer of warranties and limitation of liability provided above shall be interpreted in a manner that, to the extent possible, most closely approximates an absolute disclaimer and waiver of all liability.