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Revision as of 07:40, 22 January 2018 by Nicorikken (talk | contribs) (Update based on new flash)
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The wiki is being retired!

Documentation is now handled by the same processes we use for code: Add something to the Documentation/ directory in the coreboot repo, and it will be rendered to Contributions welcome!


The W520 comes in 4 quad-core configurations, and 1 dual-core configuration. The quad-core configurations support RAM up to 32GB.

Compared to the superseding W530 model it notably features the conventional keyboard, an eSATA port, and full-size DisplayPort connector.

For more detailed specifications, please refer to the ThinkWiki

Work in progress

Getting the W520 to work is still a work in progress. In November 2016 Charlotte Plusplus has made an initial attempt (mailinglist posts) based on the T520 firmware, with added romstage additions for ram init. This patch was committed in full to the mailing list, but not as a diff to the Gerrit infrastructure. Starting January 2018 Nico Rikken has flashed a W520 based on the T520 firmware, with promising results.

Proprietary components status

  • CPU Microcode (optional)
  • VGA Option ROM (optional): the native graphics initialization tested gave video artifacts in SeaBIOS. When using VGA Bios there were none.
  • ME(Management Engine) => you do not have to touch it (just leave it where it is). Also the stripped down T420 version can be re-used.
  • EC(Embedded Controller) => you do not have to touch it (just leave it where it is)

Coreboot patch

An archive containing the W520 board support was posted on the Coreboot mailinglist. The patchset is based on the T520, but romstage additions for ram init were required.

Known issues

  • RAM Init seems to cause issues (discussion thread).
  • Native VGA init is not working reliably (discussion thread).
  • The coreboot configuration consumes more power than the vendor BIOS does, so some additional settings might be required. (discussion thread).
  • No ACPI event when (dis)connecting the bay.

Straight T520 firmware

An attempt in January 2018 based on the T520 firmware, with stripped Management Engine, SeaBIOS as payload, and a copied IFD. Video BIOS Table was not tried.

Known issues

  • Only two of the four DIMM slots work correctly:
    • The deapest one underneath the keyboard (2 nested slots present)
    • The black one from underneath the case (2 slots side-by-side present)
  • The 2 USB 3.0 slots on the side are not working for boot media, just the USB 2.0 slot on the back.
  • WIFI card needs replacement for a blob-free one.


  • CPU (4 cores, 8 threads)
  • Suspend and resume
  • Ethernet port (GbE blob was put into place)
  • Speakers
  • Webcam (which is an internal USB-device)
  • 2 RAM-slots

Next steps for improvement

  • Replacing WIFI card for verification
  • Work on Native RAMinit to support 4 slots and in different configurations.
  • Trying Video Bios Table
  • Verifying issues noted by Charlotte Plusplus


The location of the chip is similar to the T520:


When flashing with a Raspberry Pi no external power is needed. The 3V source from the GPIO is sufficient. The pins WP and HOLD can be left floating.

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