[coreboot] Lenovo X200 running Coreboot drains 3-4W more power than with Vendor BIOS

[Daniel Kulesz]

Hi again,

I did some more experiments with the vendor BIOS and made the following observations:

- disabling "cpu power management" makes the idle consumption raise to 12,8W
- disabling "PCI Bus power management" and "PCI express power management" makes the idle consumption raise to 13,3W
- disabling the AMT firmware had no effect
- running the stress test still drains only 24,2W
- performance is the same as before

I still don't understand the whole performance issue. Therefore, I took another X200 with a P8600, CCFL screen and an older vendor BIOS and re-ran the benchmark there --- with almost identical results.

So in the end I'm just confused. This would mean that running Coreboot makes the X200 *much* faster at the expense of battery life, both in idle and under stress conditions.

Any ideas which could solve this mystery?

Cheers, Daniel