I have a spare motherboard that I'm setting up for studying this noise issue by pinpointing from which component it comes from - BTW how would it be possible to have an autopower on option ? I mean, as soon as the AC adapter is connecter, start booting - because I don't have a spare keyboard for this spare motherboard :-)
Some remarks on a X60t using a SSD ie quite silent :
- I have tried physically removing the modem - this introduces a similar (but less intense) noise using the default bios
- with the x60t on an ultrabase and coreboot, the same noise is heard until say 30 minutes, then it become silent - I suppose because of the fan turning on due to the high temperature or automatic power saving features (acpi -t report 52 C and 55 C while the CPU load is almost 0)
- What's more interesting is then, on this silent X60t, running rmmod uhci_hcd changes nothing but doing insmod uhci_hcd after that reintroduces the noise !!
- Even better, as reported on
http://www.kernelconcepts.de/~nils/ibm-x60.html, the UHCI interaction with ACPI C3 has been a problem in the past :
>"Since 2.6.24 has been released I tried it with some interesting results...
>
>The new power saving features like cpuidle and AC97 suspend did not show any >results - at first. The reason was that the CPU did almost never enter C3 when idle >which cause additional 3W (!) of power drain.
>
>The reason is seemingly a change in the USB UHCI - if I remove uhci_hcd the >CPU goes to C3 again. Strangely this was not necessary with 2.6.22 :("
I will try to read the old patches - maybe the current day uhci module is not playing nice with acpi on the X60 - for example, going into the adequate power saving mode only when some specific condition happens (like on the ultrabase), but by default going into a power saving mode that make this noise.
If someone else is interested in making coreboot work perfectly on the x60tablet, I would be willing to donate a working motherboard (with wifi module)