you generally set the comp not to turn off, but to hibernate or sleep. the power supply is wired to 12V constant on, so its not an issue. right now it takes my current HU about 20 - 30 seconds to boot up and read my thumbdrive and link to my phone via bluetooth. that is about the same that my Carputer took to wake up. you can use a laptop or net book for the same thing just fyi...