Hi Michael, On Sunday 07 October 2012 11:58:23 Michael wrote: > in BIOS I have an option to select Graphics between switchable and > discrete. When switching to discrete, the intel VGA controller > disappears completely from lspci. This makes me thinking that there must > be an additional hardware multiplexer in my machine??? Am I right, that > those hardware MUXes are usually switched using ACPI? It would really be > nice to find out, which ACPI command switches the MUX in either > direction. Switching off the nvidia card already works even though i am > using the proprietary driver, as the nouveau driver seems not to support > my card good enough. The Lenovo enterprise laptops (like the Thinkpad W520) have the same options for choosing between discrete/integrated/optimus (and maybe even switchable graphics, but I am not sure on that). These machines have a hardware multiplexer I guess, otherwise it is not possible to provide those options.
ACPI is a subsystem that also communicates with the BIOS, but I doubt that you can switch graphics on-the-fly. > Attached you can find my DSDT, which might be interesting for your > projects as well. Please provide the raw acpidump output, there might be more relevant tables like SSDT. Do it for the different BIOS settings, I have seen an Acer laptop that shows different ACPI tables depending on whether the discrete/integrated/optimus mode is in use. Regards, Peter _______________________________________________ Mailing list: https://launchpad.net/~hybrid-graphics-linux Post to : hybrid-graphics-linux@lists.launchpad.net Unsubscribe : https://launchpad.net/~hybrid-graphics-linux More help : https://help.launchpad.net/ListHelp
