It's very easy actually... They are just rebooting the system and then putting it into standby/hibernating. Easy Idea, but effective. And no need for a new Motherboard ;-)

http://bigfatflat.net/public/fastboot.bat

REM *** fastboot.bat v0.1 *** 081113
REM
REM ASRock InstantBoot Batch-File Emulation
REM Call fastboot.bat in a link with ACPISTATE
REM Parameter S3 or S4 - fastboot.bat [S3,S4] and
REM also put into your autostart without params.

No you don't :)

As I understand from their diagram they are, probably quietly, rebooting the system and putting it immediately into an suspend state afterwards.

So I emulated their technique with a batch file.

http://bigfatflat.net/public/fastboot.bat

REM *** fastboot.bat v0.1 *** 081113
REM
REM ASRock InstantBoot Batch-File Emulation
REM Call fastboot.bat in a link with ACPISTATE
REM Parameter S3 or S4 - fastboot.bat [S3,S4] and
REM also put into your autostart without params.
REM
REM It's a good Idea, but they are also just cooking with water *g*
REM They reboot the system and put it immediatly after the fresh boot
REM into a Standby/Hibernation state.
REM
REM So you can shutdown your computer it will be fresh booted and is in
REM waiting state for the new day.
REM
REM Because I like to automate things and I liked the Idea very
REM much, I decided to emulate it. :)
REM
REM The 'easy' Ideas everyone thinks after, damned that could be from me,
REM are mostly the best :) Enjoy! >> Usage below...
REM
REM And by the way... use it on your own risk! Don't blame me if you
REM cant read and understand or are unable to use your favourite search
REM engine.
[...]