Switcheroo or ACPI call: Which is the better option and what are the differences?
I have used both on my 4820TG. Near as I can tell I go from 4.5 to 5 hours on battery with acpi_call to 4 hours with vga_switcheroo. Wifi on, basic web browsing stuff.
With vga_switcheroo suspend works whether the ATI is on or off. I do not use the ATI in linux at this time, just windows for gaming. However if I hibernate with the ATI off, when the machine awakens the ATI is on and cannot now be shut down without a reboot.
acpi_call simply results in a hang when suspending or hibernating.