Possible Hardware problem…
I built a pfSense router today and the installation went smoothly, I noticed that when I connect myself to it via LAN that it keeps me connected for a few minutes, then it disconnects me. I've done a factory reset and that didn't work either. It was working last night but then it just stopped existing.
CPU: Pentium G3260
RAM: Kingston 4GB DDR3
1st NIC: Realtek RTL8111G
2nd NIC: TP-LINK TG-3468
The pfSense machine is still running when this happens, I believe it may be the NIC since I heard Realtek may have problems.
This isn't helpful for your current situation, but if you ever get the choice, just get Intel NICs.
Might want to try 2.3, newer base OS has some fixes in the Realtek driver.
Is this perhaps owed to a power saving option inside in the BIOS?
Maybe. Chipset would be nice to know.
Also: Post dmesg Please.
@devs: Does the pfsense-FreeBSD-kernel support alpm (Agressive Link Power Management)?