1 2 Previous Next 28 Replies Latest reply on Feb 1, 2011 5:56 PM by

    DP55KG lan issue


      I need some help with a lan issue with the DP55KG motherboard. I have an entire gigabit network (modem, router, and switch) but the onboard nic of this motherboard refuses to connect at any speed higher than 10mb/s. I have tried both auto negotiation to forced full duplex gigabit, nothing works. In fact if I switch from any thing other than 10mb/s I get total connection loss. The nic's diagnostic test reports that every thing is fine except that the "link partner" cannot achive anthing higher than 10mb/s. I hooked up another pc and laptop to the switch using the same cable (cat6), same port and achived 1gb/s without a hitch. Ran tests with other cat6 cables on other ports, even bypassed the switch, still nothing. The system is a fresh install of vista x64 that's been fully updated. I've tried both the lan drivers supplied with the motherboard, and the newer ones off Intel's web site to no avail. I'm starting to think that the nic is self is defective. I really would hate that concidering that this is the second DP55KG I've worked with, the first having a bad coil. I'd hate to have to go throught a second RMA. Anyone have any ideas before a second tear down?

        • 1. Re: DP55KG lan issue

          I do have the exact same problem: I installed Windows 7 64-Bit from the MSDN AA  on my shiny new DP55KG yesterday and am stuck with 10mbit/s ever since. As you outlined, there is not a single chance of changing the nic speed to anything above 10mbit/s, no matter what configuration is made. I have tried various switches / routers already. I am using driver version of the LANPro 64-Bit driver and the latest publicly available BIOS (3822).

          • 2. Re: DP55KG lan issue

            Same here. I'm pretty sure it's a bug introduced with the latest BIOS. Did you also flash to KGIBX10J.86A from 9/25? I know I had no problems before. I was however able to set the network speed manually to 100mbit, thus I can at least make full use of my internet connection, if not of my intranet.

            Maybe I'll try to downgrade the BIOS to the previous version, don't know if the board allows it. If I find anything usefull I'll post it.



            I flashed to the previous BIOS but it didn't resolve the problem. Don't know what to do now, either.


            Update 2:

            Measuring the network speed I found out that changing manually to 100mbit doesn't do a thing for me, the connection isn't faster than 10mbit.

            Also, I have two installations on this PC: Win Vista x64 and Win 7 x64; while I still mainly use Vista for work and haven't touched Win 7 in 14 days I still have the exact same issue under Win 7. So this is a hardware problem for sure. I also tried 3 different cables, among them one which connects my Mac Mini to the router with 1 Gbit without problems.

            • 3. Re: DP55KG lan issue

              Thanks for the responses. Yeah, I have the latest BIOS and all the latest drivers installed. Curious odysseuscm that you can set to 100mbps manually, but as stated before, I can only set to 10mbps. Any other setting causes my connection to drop completely. I reserched the lan chipset. I see that it's the Intel 82578DC, on the LGA1156 server side of things it's the Intel 82578DM. So, I downloaded the drivers for the server boards (S3420GP) and installed those. They went in without a hitch, the installer even detected that I have the 82578DC, but I still only get a 10mbps connection. I've tried just about everything at this point.

              No other computer on my network is having this problem. Even my old trusty D975XBX2 is running at full gigabit speed. It has to be a problem with this boards BIOS or drivers (I suspect the drivers). I find it hard to believe that all of us have a bad lan chipset, or atleast I hope that's not the case. I'll keep checking back here and updating as I find things. Hopefully this problem can be resolved soon.


              Update: I just tried to email support, but the drop down menus where you select your product have the DX58SO as the only selectable 5-series motherboard. Ah! The joys of being an early adopter! I guess I'll have to wait till monday for live chat.

              • 4. Re: DP55KG lan issue

                same issue on my DP55WB. I'm pretty sure it was working fine a few weeks ago, I think it was introduced in new bios.

                tried to install a different OS (win 2008 R2), same 10Mb issue. tried different cables, different switches, etc...


                seems to be a bios issue?

                • 5. Re: DP55KG lan issue

                  I have a brand new DP55WB built last Friday with all new parts and flashed to the newest BIOS and newest network drivers.  Will only run at 10mbps even if you lock connection to 100mbps.  Had to plug in an ethernet to USB 2 adaptor and can still only get 20mbps from our on site server.  Used to get 60mbps.  Running Win XP.  Hope they fix this soon.  Bought Intel for reliability and stability.  Probably never again.  And haven't checked yet on the RAID dropouts mentioned on other posts.

                  • 6. Re: DP55KG lan issue

                    Since everyone who has this problem has flashed to the latest bios (which according to the release notes included an V1.2 of the LAN option ROM)  I guess we can be dead sure that the problem was introduced by that. I know for certain that I had 1 Gbit speed before.

                    Now how do we let Intel support know quickly? They should pull that bios from their servers and release a fixed version soon. As ProphetSix said, the new DP55 mainboards are not even in the support system, yet. Do they read these forums? I need full network speed fast, but I don't want to buy an extra network adapter just because they screwed up                         .

                    • 7. Re: DP55KG lan issue

                      I totally agree with you concerning the severity of the situation. I would very much like to have 1000mb/s again. I do not think that we can rely on Intel reading these forums. Even if they did, they might not notice a thread, which has < 10 posts until now. I will try to see, which methods of communication might be suitable later today. Furtheremore, I will reflash with an ealier BIOS release later today, too.

                      Update concerning LAN-speed: Few posts ago somebody noticed, that he was able to set his port to 100mb/s full and still he only got 10mb/s speed. I am able to tell, that I share this experience. I tried to manually set to 100mb/s full, too and only got few bytes/s. However, when I set the port to a horribly wrong 100mb/s half (!) the port started to act at real a 100mb/s. Thankfully my switch is able to handle this stupid setting.

                      Bottom line: The maximum speed, which you can get with both lastest BIOS and drivers is 100mb/s when setting the ports to a manual 100mb/s half-duplex (!).

                      I will keep you updated as soon as there are further findings to share.

                      • 8. Re: DP55KG lan issue

                        I just chatted with someone on live support (it actually works!). This is our conversation:


                        vliebingerx-s : Hello. Thank you for visiting Intel Customer Support. How can I help?

                        you: Hello. After upgrading my mainboard to the latest bios the LAN chip only works at 10 mbit

                        you: I'm not the only one. Several users of DP55 boards report the same issue

                        you: http://communities.intel.com/message/69963

                        vliebingerx-s : Yes, we have some cases reported and we are currently working on this.

                        you: that's nice to hear. is there a time window for a fix?

                        vliebingerx-s : Unfortunately not at this time, it is being studied to find the reason, once the reason is found, there could be an ETA on the BIOS update that will fix this, but unfortunately engineering has not provided us with any data.

                        vliebingerx-s : I'm pretty sure that it should not take a long time.

                        • 9. Re: DP55KG lan issue

                          I have been using this free BW meter watching the speeds on this device




                          Showing very low speeds of only 2-3mbps.  Will try the half duplex fix later.  Thanks for your call to them.

                          • 10. Re: DP55KG lan issue

                            Setting to 100 half duplex works for me as well and at least allows me to max out my internet connection (20 mbit). So as a temporary fix it will have to do.

                            • 11. Re: DP55KG lan issue

                              This is a relief, I thought Intel's chip followed the fate of marvell Gb chip on my old asus p5pe-vm, which fried after a month of average usage. Just to confirm, my DP55WG is in exact same state, latest dirver, both on win 7 64bit and XP 32, all tests are fine, defaults to 10Mbps because the gigabit router on the other side isn't capable of anything faster, can force to 100 full duplex, but forcing to gigabit kills it. Needless to say, I am running the updated bios.

                              • 12. Re: DP55KG lan issue

                                Well it's nice to see we are making some headway on this problem. Thanks to odysseuscm for being proactive with the tech support chat. I too can confirm razn0r's findings...setting to 100mb/s Half duplex is working. Not the best solution, but the only one we seem to have for now. Hopefully they will get this problem fixed in short order. I too, as others have said, bought this board for intel stability and for the...wait for it...the intel lan chipset! They have some of the best networking products and their boards are one of the very few ways to get one built-in. Makes this problem particularly amusing for me. Being that this is their top of the line product, outside the X58, hopefully we'll have a fix shortly. Keep up the good work people...check back later.

                                • 13. Re: DP55KG lan issue

                                  I just finished chatting with intel's CS, they advised to switch back to the old bios for now, which, in my case, was the one from august. I'll try that, but doubt it will work.

                                  • 14. Re: DP55KG lan issue

                                    @skhudav let me know if the downgrade works for you, it didn't do a thing for me...

                                    1 2 Previous Next