The Acer Aspire One has a built-in BIOS recovery routine, which can boot
into a minimal BIOS environment via a special boot block to re-flash
the BIOS, even if the system does not pass POST and does otherwise not
boot anymore. This is also known as crisis disk mode.
First format an USB flash drive with FAT. It does not need to be
Download the latest
BIOS, and extract all files from the zip file. Put both FLASHIT.EXE and
the BIOS file with FD suffix in the root directory of the flash drive.
The files must not be in a folder. Rename the BIOS file to ZG5IA32.FD
before proceeding. It only works with this exact filename.
Turn the AA1 off, with the flash drive still connected, and make sure
both battery and AC adapter are also connected.
simultaneously, keep them pressed and
press the power button. Release Fn+Esc after a few seconds. The power
button starts blinking at this point. Press the power button once. The
AA1 will now initiate flashing the BIOS. After a while the button stops
blinking, and the AA1 reboots shortly after. Wait patiently.
If it doesn't reboot by itself, but keeps blinking, wait at least a few
minutes before turning it off, and try again.