[pfSense Support] Throughput calculation

[Ebay]

Title: redundant wan router

I am using an MSI motherboard with a 2 gig Celeron processor, 512 megs ram, and 3ea realtec gigabit network cards.  Does anyone know what kinda thoughput would be possible in this configuration.  I need to route between two local networks.  Is there any documentation that explanes some examples I could achieve with certain hardware types?  Thanks Again.  >>Ryan