W520: warning don't load latest firmware 1.25

[plympton]

It disables turbo boost. Reverting to 1.06 restores turbo boost functionality.

Went through most of yesterday wondering why my machine was dog slow never going above 2.2 ghz, and a quick Google search revealed the answer. Oh well, so much for rigorous testing before release....

[KongMD]

There's actually a five-page thread over on the Lenovo forums about this. Some interesting stuff was found, but the bottom line is that you have to revert to a previous BIOS edition to get TurboBoost. Also, it doesn't work when the laptop is unplugged (by design, unfortunately). Lenovo forum staff have escalated the issue to engineering, and there will probably be a fix some time soon

The BIOS edition I've been using with TurboBoost successfully is version 1.06. The download is at the very bottom of the BIOS utility page.

[pkincy]

Actually 1.22 works just fine. You certainly can roll back to 1.06 but don't need to. Just back to 1.22 from 1.25(1.24).

[plympton]

I bumped back up to 1.21 today, and will go to 1.22 based on your response. Felt like 1.06 was either running hot or just spinning the fans continuously.