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

[Nico Huber]

Hi Daniel,

On 01.05.2016 12:26, Daniel Kulesz via coreboot wrote:
> Coreboot with idle=poll: 15,8W
> Coreboot running "stress": 37,2W
well, this is what I would expect from the specs.

> Vendor BIOS with idle=poll: 15W
> Vendor BIOS with intel_pstate=disabled: 10W
> Vendor BIOS running "stress": 24,3W (!!)
This looks suspicious. Doing some calculation:
You are measuring at the wall plug, efficiency could be around 83%,
which would leave 20W. Chipset, backlight and other stuff needs power as
well, say around 8W, leaving 12W for your 25W TDP CPU???

So, before bothering yourself with the power consumption difference
under load, I would also check the performance of coreboot vs. vendor
BIOS.

> And I didn't find any documentation about how to actually extract the
> VGA Bios part, so any hints are welcome.
Um, if you find a way, please document ;)

Nico