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Wednesday, March 17, 2010

Troubleshooting Multi-Player PC Game Connectivity Issues

Here lies the original post that started this blog, a troubleshooting guide for PC gamers. This guide provides suggestions for possible solutions to common, and not so common connectivity problems.

The suggestions are presented in a form generalized enough to prevent the document from becoming a book (and it's already plenty long), but not so much so that they become useless.

Using these suggestions with the details provided, along with resources on the web, your hardware and software documentation and Google should you need to do low-level changes where step-by-step details would have been impractical to provide for reasons of document length or where steps vary wildly for differing equipment, you should be able to resolve your connection problems.

Regardless, do note that this is not for the faint of heart: there is a lot of ground to cover and many subtleties regarding PC game connectivity and issues involved in troubleshooting problems.

You can view the current incarnation of this document at:

Please leave any comments and suggestions here, or via e-mail as shown in the document.


  1. That is awesome Rob. Found this on the EA Forum.

    I still have to read trough all of it to solve my rubberbanding problem. I know it's not FPS relate (I get 70+ fps on BC2) and my ping is relatively slow. (I do connect to server near where I live)

    Also, it appears I have the same problem on other MP games (especially Team Fortress 2). Low ping, high FPS, but people usually tell me I'm rubberbanding all over the place.

    I know it shouldn't show any problems but I tried using speedtest.net and pingtest.net and both gave me good grades.

    Anyway, I'll try what your guide says and let's see if that works!

    Thanks Rob!

  2. @kurashu:
    You might want to look at your sound system and settings. Some sound systems (or their drivers) seem to clobber the audio rendering thread in BFBC2. Try setting your in-game setting to headphone, this seems to lessen the load. Update your sound drivers. Try turning off your sound system in BIOS, see if the rubber-banding stops. If so, you've isolated the issue. An add-in sound card, or external USB device/headphones might work for you.

  3. Unreal amount of work you did on that. Took a wahile to read, but I ended up solving my issue using it, turned out the network address translation was incorrectly set on it. I'm not sure why this seems to break Bad Co. 2 for some people - don't care really, the info you gave me helped me to fix it.
    Thanks a bundle!

  4. Thank you! I read the newspaper, and it has solved a problem I had with many games. Hamachi was breaking them, I pulled the adapter and now everything is good. Forgive me the words that I have I am using Google Translator to German.

  5. YOU ROCK!
    Ive been trying everything on the us and uk forums - forwading ports dmz you name it.
    NOTHING worked. It took us a while to read this (maybe you could make a simple flow chart? just an idea) but it turned out to be the routr had wrong nat set. Changed it, BANG - all of the problems stoped. Me and my dad have been playing non-stop. Thanks for doing all that work - EA should hire you - lol !


  6. Excellent read. Found out about it at bash and slash forums, guy there called it a must read. I agree. I wasn't having any problems with the game I'm playing (bad company 2), but the post title of to port forward or not to port forward in bfbc2 caught my eye.
    Posted a link in our clan forums.
    Saw it also in EA forum - too bad that thedemonslick poster is such a dork. Maybe he gets money from portforward.com :-)

    thanks for taking the time to make this.

  7. heycarnut has the answer (thank you sir!). It is the audio (sound card) that is causing frame shuttering or rubber banding. I seem to remember back in the day when BF2 first came out and my sound card was on its last leg, I started getting heavy frame shuttering/rubber banding and it turned out to be the audio card and drivers.


    "heycarnut said...
    You might want to look at your sound system and settings. Some sound systems (or their drivers) seem to clobber the audio rendering thread in BFBC2. Try setting your in-game setting to headphone, this seems to lessen the load. Update your sound drivers. Try turning off your sound system in BIOS, see if the rubber-banding stops. If so, you've isolated the issue. An add-in sound card, or external USB device/headphones might work for you."

  8. In one of your articles you mention that 100kbps is enough bandwidth for any game out there. I just received my copy of Battlefield 3 and for online connection requirements it says "1 MB DSL KBPS or faster internet connection." What does that mean? What does KBPS stand for? My understanding is that the game requires a 1MB/s connection. Is that correct?

  9. @Anonymous 10/31/11 17:03:

    I have not looked at a retail box - is that verbatim?

    "1 MB DSL KBPS " is probably a typo or similar error - there is no such string that makes any logical sense.

    Without getting overly pedantic (e.g., K vs k vs Ki) KBPS means ~1000 Bytes per Second (KiloBytes Per Second).

    Now, the 1MB would mean 1 million bytes. If in fact the game actually required such bandwidth, much of the world would be excluded from playing it, and a goodly percentage of players would run into bandwidth caps from their ISPs pretty quickly (e.g. Comcast cap would be at ~70 hours of play per month, not including any other bandwidth used).

    I think we can safely assume this is not the case, and that the figure is either a typo (they may have meant 1Mb (1 MegaBit, ~125Kb), a gross overestimate to ensure customers have an order of magnitude margin, or a combination of the two.

    I see no evidence BF3 requires any more bandwidth than can be provided by even a lower-tier DSL connection, and have successfully tested it over a fairly low-speed cellular net connection.


  10. i have problem whith bf3 on pc i lag every second but is not my conection somthink on my desktop my pc was OS windows 7 , grafics Nvidia 9800gt , cpu intel core i5 660 , ram 2 gb , hd 1tb what can i change to play it normal?

  11. @Anonymous 11/01/11 12:39:
    You'll probably have better luck getting overall game performance help in the EA BF3 forums, I don't really do much game performance work anymore outside of networking. That said, your specifications are on the low side, as I'm sure you are aware. Most game publishers are notoriously optimistic when specifying the low-end requirements. If you've excluded "lag" as in a network symptom, then I'll assume you mean overall game performance, specifically the rendering. This is a pretty demanding game. Even on low settings, a dual-core system will be pressed, particularly at higher resolutions, e.g., 2560x1600, and perhaps even 1920x1200 might be non-starters with your specs. Try dropping everything to minimum specs, and lowering your resolution, see what you get. Then start bumping things up to get an acceptable balance. Do note - the HBAO option is pretty expensive, I've seen it cut FPS in nearly half on some machines. Also fiddle with audio settings where applicable - the audio rendering thread(s) in some games can tax a dual-core system a stall out other game threads, causing "stutter". Good luck, do report back if you make progress, sorry I can't give you a silver bullet for this one.


  12. @heycarnut

    Yes, that's verbatim from the back of the retail box. I know what KBPS means but it doesn't make sense the way they wrote it.

    My connection is 15mbps generally but it does go lower at peak times and when I played the Battlefield 3 Beta on Caspian Border with 64 players, I was laggying all over the place and others were as well. Could it have been due to the server not being capable of running 64 players on such a large map or do you think it was due to my internet connection?

  13. @Anonymous 11/01/11 12:18:
    You can run some tests on your connection (try e.g. the tests at dslreports.com) to check that your line is stable, and the ping/jitter tests at speedtest.net are decent. Assuming your connection is decently stable, and the ISP is not throttling (Canadian ISP are notorious for throttling game traffic), the culprit is likely the server, particularly if others are complaining of similar symptoms at the same time on the same server and you do not have similar problems on smaller / less populated servers.


  14. I think it was the servers as now I don't lag much. I get the occasional rubber banding but that's very rare. Anyway, thanks for your help, Rob!

  15. @Anonymous 11/03/11 16:31:

    Glad to hear it! It is not unusual for things to be a little "sticky" the first few weeks as server / network capacities are adjusted and minor issues resolved. There was a recent server patch that specifically addressed "rubber-banding". Game on!