[RESOLVED] New Chelsio T520 running very hot



  • Hi all.

    We are running pfSense 2.2.6 on a SuperMicro 5018-FTN4 and over the weekend we replaced an Intel x520-DA2 with a Chelsio T520-LL.

    It ran for about 8 hours and then pfSense locked up because it hit the nmbufs limit.  (We had already increased the nmbclusters to 1,000,000 for our intel card and it is still set that way).  Looking at the RRD graphs, the CPU showed very high CPU interrupts for about 30 minutes before it crashed.

    We rebooted pfSense and it came back up and seems to have been working ok since, but the temp on the card is very high (reporting 90-117 C, and verified with an infrared themometer).  The normal operating temp on this card is supposed to max out at 55 C according to the docs.

    We've pulled the cover off the box and can put some additional fans on it, but I don't believe this is normal.

    Is there something I can check for, or some additional tuning I can do to bring the temps down on this card?  Or could it be a faulty card?

    Thanks for any help.




  • Cards like these are meant to run in servers with forced airflow across them. The product brief does specify that the adapter needs Airflow:200lf/m.

    You should be using the optional 40mm chassis fan in the Supermicro to help cool the adapter.



  • We are running pfSense 2.2.6 on a SuperMicro 5018-FTN4 and over the weekend we replaced an Intel x520-DA2 with a Chelsio T520-LL.

    If you buy an appliance from the pfSense store like the C2758 1U or XG-2758 and an additional Chelsio
    adapter they will mount an additional fan and bracket inside of that unit. So I assume you should mount
    also a second fan inside  of your unit to coll it right down!

    It ran for about 8 hours and then pfSense locked up because it hit the nmbufs limit.

    In some rarely cases it could be that you will need more then the mbuf size of 1 million and in other
    cases perhaps only a size such 65000 this should be set by yours and monitored then over days what
    is going on and what is in exactly your case the right number of size.

    (We had already increased the nmbclusters to 1,000,000 for our intel card and it is still set that way). 
    Looking at the RRD graphs, the CPU showed very high CPU interrupts for about 30 minutes before it crashed.

    How many RAM is installed inside of that box? I mean how many GBs of RAM is there inside?

    We rebooted pfSense and it came back up and seems to have been working ok since, but the temp on the card is very high (reporting 90-117 C, and verified with an infrared themometer).  The normal operating temp on this card is supposed to max out at 55 C according to the docs.

    With the reboot the mubuf size space will be flushed and is fresh and free for sure.
    What is the ambient temperature of that pfSense box?
    What is the temperature inside of that box?
    Is it in a rack that is actively cooled or not?
    Is this inside of a climate server room or not?

    We've pulled the cover off the box and can put some additional fans on it, but I don't believe this is normal.

    Yes it is, if the pfSense shop is offering that second case fan with an additional bracket it makes sense.

    Is there something I can check for, or some additional tuning I can do to bring the temps down on this card?  Or could it be a faulty card?

    A climate server room is the best, it cools all down! It is very high in price for electric power but the
    best you can get for your equipment. We cool down till 20 C (Celsius) and count + 10 inside of the rack
    and appliances and mostly the critical temperature for all servers and other appliances is by default 33 C
    (Celsius) but a fully climate or cooled rack should be also really nice in the summer time.

    Otherwise you should be installing more fans inside or saddle over to one of the named above solutions.



  • Thanks for your response.  I believe adding an additional cooling fan will solve this issue.  We put an external fan blowing air across the top of the open supermicro box and it brought the card temp down to ~60 C.  I'll get the additional supermicro fan and install that in the box.

    This is in a climate controlled server room (~68 F/20 C), but not a climate controlled rack.  We were running it with the single cooling fan that comes with the bare 5018-FTN4 system, and had been using an intel X520-DA2 10g card for at least a year with no issues (though only 1 of the 10g ports were being used), so we assumed it would be a simple swap out.  We are using both 10g ports on the Chelsio card, and apparently it runs much hotter.



  • I've just checked mine t520-so-cr in a 1u case with four 1u fans pulling air over a c2758f. CPU is 45-50 and t520 is 45. I previously used the intel x520 which ran much cooler I recall.