I have just bought an Acer Aspire E1-571. I changed uts bios settings to legacy bios, removed windows 8 and installed Linux on it. Now every day, when I turn it on, it restarts with bios settings back to defaults, and I have to set legacy bios anew, in order for the notebook to boot.
Since I use my notebook at home, I removed the battery and use it with my house normal power line.
I am having the same problem. As soon as I remove the battery pack and/or unplug the computer from mains power, all BIOS settings are lost. The RTC CR2032 battery is not to blame, as opening the notebook to remove and test it revealed it was fully charged. I swapped it for a new one nonetheless, which accomplished nothing.
I bought a 1 TB hard drive which I installed Windows 7 x64 on, and expanded the RAM amount to 16 GB, but that's irrelevant because this issue was already occuring with the OEM Windows 8 and hardware.