FW13 AMD loses BIOS settings when main battery runs out

[Wrybill_Plover]

I just had the main battery run out for the first time since I got the FW13 AMD. Running NixOS, I left it suspended for a couple of days when the battery was relatively low, and it was dead when I finally got back to it.

Once I recharged it and turned it on, it took quite a while to get to the FW splash screen, just as it did initially after the RAM was installed. Checking the BIOS, I found that some of the settings were reset to their defaults: the UMA size was back to Auto, and the RTC was lost. Some were retained, however: the power LED brightness, and the disabled Secure Boot.

My question is: is that an expected behavior?

[druneau]

Hi!

I believe I read something somewhere about the main battery being the only battery in the device. So this would mean it’s being used as the CMOS battery aswell.

So a full drain would indeed result in loosing bios configuration… I don’t know if that’s good or bad. I guess it’s a tradeoff.

EDIT: Here’s where I read this: Does the Framework Laptop 13 (AMD Ryzen 7040 Series) include a RTC/CMOS battery on the mainboard?

[Wrybill_Plover]

@druneau

So a full drain would indeed result in loosing bios configuration… I don’t know if that’s good or bad. I guess it’s a tradeoff.

EDIT: Here’s where I read this: Does the Framework Laptop 13 (AMD Ryzen 7040 Series) include a RTC/CMOS battery on the mainboard?

Thanks for that link! Makes sense. I knew that it was not very healthy for the battery to be completely drained in general, but now I have another reason to try to avoid that as much as possible.