DDR4 is still a good choice for budget PCs

At some point, biters almost always overwhelm my defenses

you need to have a wall of gun turrets fed by a ammo belt, all around the base. They will shred through all biters.

My tank gets destroyed before i can do any damage.

I haven’t traveled to other planets yet.

How do you kill the medium demolishers?

Its team fortress, not titanfall2

RX 560 runs at 50w and can run old games at 1080p

Tom(4K) is too heavy for the tiny bed(RX 560) which is struggling to keep up with his weight.

What do you mean?