Linux Kernel in a Nutshell

Name

acpi_sleep — ACPI sleep options.

Synopsis

acpi_sleep=[s3_bios],[s3_mode]

During S3 resume (which happens after the machine has been suspended to RAM), hardware needs to be reinitialized properly. For most devices this is simple, except for video cards, which are normally initialized by the BIOS. The kernel does not have enough information to restore the video device, because that information is in the BIOS and not accessable at all. This option lets the kernel try to use the ACPI subsystem to restore the video card in two different ways.

See the file Documentation/power/video.txt for more information on this option and how to find the proper value for your type of hardware.