Yeah … Linux would be your friend here.

My laptop is a shitty old chromebook from 2016 that was low-spec even at that time. 2-core CPU, 4GB total RAM, 14GB total storage(!). But I’ve got a chromebook-specific Linux distro on it, and it works great even in 2026, does everything I need it to, and never even feels slow or laggy. (Also has astounding battery life as well, oddly enough. ~17 hours, with the original 2016 battery.)

I don’t know what ‘resource-intensive tasks’ you need to do, but if you want to free up hardware on an old, low-spec machine, Linux is your best and only friend.