What browser are you using? I have a similar old Pentium Dual Core E2140 1.60GHz and Firefox opens fast enough on Linux. I guess the HD is the thing that makes it slow.

I tried Firefox and Chrome. Both were slow to open. I just loaded up
MintLinux and a 1tb ssd. Still slow although boot time decreased.

Should be fast enough for a BBS. But hows the power consumption when
idle? Isn't it a waste of energy?

Probably. I have 7 computers running at the moment so I never really gave
power consumption much thought. Utlities are a business expense so tax deductible. I'll network that guy to the rest of the boxes and use it for
file storage.

--- Mystic BBS v1.12 A46 2020/08/26 (Raspberry Pi/32)
* Origin: The Lab BBS (21:3/105.3)