If it's what I think you're talking about it's a front control module.

Technically it's not a fuse block anymore, last thing I knew they were calling it a Totally Integrated Power Module aka TIPM or Integrated Power Module aka IPM.

Everything is a computer anymore. lol

Usually the thing on the side that has an aluminum cover is the front module (controls headlights among other things).

I've sold a few of them when I parted out some Ram trucks from that era to people who were having headlight problems.