@Guillaurent said in Intel Celeron N2830 as 2.5Gbps router:

Celeron N2830

Yes, that's a 10 year old CPU. I would look at something newer if you;re buying a new device.

I'd guess, because I've not tested that personally, that it wouldn't pass 2.5G in pfSense. It might do 2G but there wouldn't be much overhead.