Manipulation performed under Windows XP professionnal SP2
- At startup enter the BIOS by pressing DEL
- Once in the BIOS go into Power Mangement >set up
- Go to Resume by alarm and set it as Enable
- Go into Date (of month) Alarm and enter the date of your choice
- Go in Time (hh: mm: ss) Alarm and enter the time at which you want your PC to start automatically
- Save the settings and exit the BIOS
Thanks to BOB73 for this tip.