Slow speed when switching to Intel Nics



  • Hi guys, im hoping you can help me out, this is very frustrating.

    I had PFsense up and running and working fine with the onboard Realtek NIC for Wan an an PCIe Intel Nic for LAN.  I was wanting to get rid of the Realtek as i wanted to run only Intel Nics.  I went out and bought another Intel Nic PCIe and made it my Wan port.  Ever since then my Internet went from 50Mbs with the Realtek to 5Mbs with the Intel.  I was running no VPN, no packages, just a plain install.

    I tried it in different slots, nothing changed.  I even put that card in my home PC and ran it right to my cable modem and i get back up to 50Mbs so the card is fine.  As soon as i plug it back into PFsense, it goes back down to 3-5Mbs.

    Each time i switch cards, my Wan IP changes, i guess because the different NICs mac address. I though maybe it was a weird IP but that same IP works perfect in my home computer. It is something with PFsense.

    If anyone can help me, i would very much appreciate it, i have spent the whole weekend on this.


  • Banned

    Have you checked the speed of both interfaces? Autoselect or forced 1000mbps full duplex?



  • Ya the Intel one wouldn't even get an IP unless I set it to 100tx full duplex. It didn't like auto.


  • Banned

    What hardware is the nic connected to? remember to set the other end to 100tx FD as well



  • It is connected to my shaw cable modem on 50Mbs service.  My pfsense box is the same that was maxing out on the Realtek.  It is a e5200 dual core cpu with a laptop hard drive, 4gb ram and 2 PCIe slots.  Ping is goes up from about 8ms to 18ms switching to the Intel and the download just tanks.  It's got to be something simple i'm missing.  Other Intel Lan card is set to 1000/full duplex and i get 105 mb/s transfers over my lan.  It's just the internet side that is screwed.

    Even disabled the Realtek thinking that there might have been a conflict.  No go..  These are Intel Gigabit CT adapters.  They work perfect everywhere but in PFsense on the Wan side where i need them :)



  • Hey guys, think i figured it out.  I did some more googling and came across one link where a guy said he had to set the connection to 100tx half duplex.  I set it to 100TX and bam, right up to 52Mbs. AWESOME.  Is there any downside to not running in full duplex?  I guess it doesn't matter as i have no choice.  the other Intel NIC is running 1000tx full duplex for the LAN.



  • @xman111:

    Is there any downside to not running in full duplex?

    That depends on your traffic profile. If you're only downloading it doesn't matter but if you wan't to upload concurrently, it will give less performance than full duplex.

    I guess it doesn't matter as i have no choice.

    Well you could go back to the Realtek that worked well for you before. ::)

    Adding a nic that doesn't work better on this relatively slow WAN-connection than what was already used, seems like a huge waste of hardware to me.

    The sligthly ridicuolous bashing of Realtek, that seems mandatory on this forum, apparently sometimes lead to bad things.



  • That is true.  I just bought into the hype.  I also have a dual gigabit Intel adapter being shipped to me from Amazon right now, it's final resting place will be my pfsense machine as i don't have any other need for a dual card. I hope it works without issue.

    I have my box setup following instructions on the AirVPN site. I basically uses 3 NICs, one for WAN, one for VPN, and one for LAN, i wanted to try to keep using that so it looks like i will need my Realtek card anyways.  I will just move the other Intels to my server and my own PC.

    Wish i didn't waste $150 on network cards when i probably only needed one.


  • Netgate

    I think it's premature to blame the intel NIC.

    Both sides need to be set to auto, or both sides need to be hard-set to the same speed/duplex.

    What is the cable modem port set to?



  • How do you tell what the cable modem port is at?

    Further developments, in case anyone cares..  A little more playing around and if I set the Intel NIC to 1000baseT (Not 1000baseT full-duplex) it reports as 1000 baseT full-duplex and connects at full speed.  I don't think i tried that option, i just tried the full duplex setting each time, never thought to try the one that didn't say full duplex.

    Now im a happy camper, just need to figure out the rest of the settings for our household needs.


  • Netgate

    @xman111:

    How do you tell what the cable modem port is at?

    Good question to direct Shaw's way.  :)

    Further developments, in case anyone cares..  A little more playing around and if I set the Intel NIC to 1000baseT (Not 1000baseT full-duplex) it reports as 1000 baseT full-duplex and connects at full speed.  I don't think i tried that option, i just tried the full duplex setting each time, never thought to try the one that didn't say full duplex.

    It's my understanding that there is no such thing as 1000BaseT half-duplex.



  • Shaw is pretty much useless!

    Weird that they have the settings for 1000BaseT and 1000BaseT full duplex..  PFsense is damn confusing!


  • Netgate

    Presuming your Intel NIC is using the em(4) driver.  From the Manual Page:

    1000baseTX  Sets 1000Mbps operation.  Only full-duplex mode is supported at this speed.

    I think they mean 1000BaseT, but you can't have everything.

    When I have gig ports talking to gig ports, I use autoselect.  If I have gig ports talking to who knows what's going to plug in, I use autoselect.  If I have something static like you have and I have a gig port talking to a 100BaseTX port, I usually hard set both sides.