BIOS vs. Embedded Controller

[Mike-NOAA]

On IBM Web sites, I see updates for both the BIOS and the Embedded Controller of Thinkpads. Are these the same? Different? If different, what is each and do they have to be kept in sync? Any other information would be welcome. I find this a bit confusing & haven't been able to come up with any good information.

[jdhurst]

I have a T, not an R, but the T has the same two things (BIOS and Embedded Controller). They are not the same, and are maintained separately. I always maintain both.

When you download either, download and read the instructions. The instructions will tell you what the prequesite is. That is, you need such and such version of BIOS to do Embedded Controller. Make sure that is so and proceed with upgrades in the correct order.

Sometimes there is a conflict. For example:
On a new T41 2373-4SU, it comes out of the box with BIOS Version 2.x and Embedded Controller 2.y. On the site is BIOS V3.04a and Embedded Controller 3.01a.

The Embedded Contoller instruction says:
- This version of Embedded Controller Program will only work with BIOS
Version 3.04a (or higher). Please get the additional package, BIOS
Version 3.04a (or higher), and update the BIOS in the system with it.
- If you need to update the BIOS as well as the Embedded Controller
Program, update Embedded Controller Program first.

In these cases, I call IBM, and again in this case I called IBM, and they suggested upgrading the BIOS to Version 3.00 (still available from IBM) and which works with Embedded controller 2.04.

I did the BIOS Version 3.00 first, then the Embedded Controller 3.01a next, then the BIOS Version 3.04a third.

I do the updates via diskette. I make all the diskettes first and label them. Then I do the updates in order without starting Windows.

Be careful. If you damage your BIOS (don't panic, you shouldn't), you could be in for a costly repair.

Document your exisiting system; Read the instructions carefully; Upgrade in the right order; and you should be fine.

Hope that helps, ... jdhurst

[Mike-NOAA]

Thank you; that is helpful.