Separate computer same jobs

Hey guys, I’m a noob with crypto mining so sorry for my ignorance.

My question is, if I have two PCs running nbminer, and they both happen to get the same job, are they working together on that job (as if they share tasks for the job 50/50) or are they basically just competing to finish the job first?

I’m currently running one instance on my laptop (RTX 2060) and one in my tower (XFX RX 460). Here’s what the numbers look like

Laptop On screen dialog box looks like it says 14MH/s On 2miner it seems to show about 20MH/s on average.

These numbers seem to vary a bit though.

On my tower On screen dialog: about 4MH/s on average. On the 2miner it seems to show about 7MH/s.

So is it worth it to run my tower? On average, it sits at about 55 kwatts/s. Whereas the laptop says about 155.

Again, I’m a noob, and I haven’t ran either of these for too long yet (maybe like 30-45 minutes? Aha) I just did this just to mess around at first but I’d love to see where this can go.