01-06-2014 11:55 AM - edited 01-06-2014 12:02 PM
I have a problem with my Lenovo Z510 that I recently bought. The Wi-Fi connectivity works fine for a while but then becomes slow and finally stops working completely. I have tried this using clean installations of Windows 7, Windows 8 and an Ubuntu 13.10 live CD (all of these are 64-bit versions).
Here is what happens exactly:
1) After a reboot, the Wi-Fi works fine for about 5-15 minutes. I am pinging my default gateway (the router) like:
ping 192.168.0.1 -t
when using Windows OS. All packets are sent successfully.
2) I measure the speed using the website speedtest.net. While the Wi-Fi is still working fine, the top download speed it achieves is 35 Mbit/s.
3) After a while, without any changes on my side, the Wi-Fi becomes slow. Speedtest top download speed drops to about 15-20 Mbit/s. However, it also seems like I can trigger the problem to appear faster by downloading something at a nearly maximum speed.
4) Pinging the default gateway fails with about 25-50% packet loss. I get messages like "Request timed out." or "Not responding" messages sent by the laptop's IP (can't remember the exact message as the computer is not in front of me right now).
5) After a few more minutes, loading any website takes way too long and sometimes never works.
6) Finally the wireless connection status becomes 'Limited connectivity'. Reconnecting to it does not work at all.
7) Using Windows troubleshooter helped a couple of times, when the actions it takes was "Resetting the wireless adapter." In these cases the Wi-Fi connectivity worked again but only for a couple of extra minutes.
8) Restarting the computer helps, again for a few minutes.
1) When using windows 7 I have installed the WLAN drivers on Lenovo's website (16.0.x.x if I remember correctly) . Then I have also tried with the latest Intel drivers (16.6.x.x) based on the wireless adapter detected in device manager (Intel Wireless-N 7260). Windows 7 did not find any drivers by itself. I have tried also with the WLAN drivers for Windows 8 provided on Lenovo's website. All of these failed to fix the issue.
2) When using Ubuntu Live CD I did not install any drivers but used the ones that came pre-installed. Still, the problem appeared after about 15 minutes.
3) When using Windows 8, the WLAN adapter was not recognized at first. I connected a LAN cable and let Windows 8 find the drivers automatically. It again detected that the Wi-Fi adapter is Intel Wireless-N 7260. The connection problem persisted and I downloaded the latest Intel WLAN drivers (using the auto-detection tool on their website). Finally I also tried the windows 8 drivers provided on Lenovo's website. All of these failed.
4) I have tried also connecting to a friend's router, which is different from mine. Still, the problem appeared.
5) I have 3 other devices at home connected wirelessly to my router without any problems. Stopping these devices makes no difference.
6) Restarting/resetting the router does not help.
7) There is no difference whether the Wi-Fi network is selected as Home(Private) or Public. I have tried enabling and disabling the file and printer sharing too.
8) Already tried this http://support.lenovo.com/en_US/downloads/detail.page?DocID=HT070623 and also selecting Maximum performance in the Power options.
I really hope that this detailed explanation will be useful and someone will be able to help me with this issue. Thank you for reading!
01-06-2014 07:58 PM
01-07-2014 01:08 AM
I had exactly same problem...I found somewhere info about insufficient power which is shared for module containing WiFi and BT (If is running WiFi and BT together). I really don't know if it is true or not, but for me helped disable BlueTooth. I know it's not system solution but if someone is not using BT, it can help.
01-07-2014 05:54 AM
Hello, the issue still persist after instaling 16.6.0... but the time before the connection is becomming slow again is bigger.
I read on intel's forum about a version 16.7.0. didn't have the time to install the newer version! I hope it works...
01-10-2014 05:20 PM - edited 01-10-2014 05:41 PM
Thank you all for the responses. @NINE, I have not had a chance to reinstall the drivers yet, since currently I am away and need to access the computer remotely. However, I am almost sure I have already tried the drivers from the links you provided. I will write here again once I double check that.
Nonetheless, I believe I had some progress with finding out extra details that may help:
- My ISP provides a Wi-Fi network being broadcast by a router whose brand and model are unknown to me but most likely it is different from mine. I follow the same steps trying to reproduce the problem I described (especially by starting/stopping downloads at high speed). So far I have not been able to break it when using this Wi-Fi network. At this point the speedtest.net download speed is around 20-28 Mbit/s.
- I connect to my own router's Wi-Fi network and attempt to reproduce the problem. In about 10-20 minutes of testing, I manage to make it slow again. Pinging the default gateway results in a packet loss (25-50%).
- Without restarting the computer or resetting the wireless adapter, I am able to connect again to the ISP Wi-Fi network. However, the speed is now 3 Mbit/s. Pinging the default gateway does not result in a packet loss, thus the ISP network is still considerably faster than the other one.
My conclusion so far:
Somehow the router is not completely compatible with the wireless adapter. It somehow manages to break the wireless adapter's normal operation, which can only be fixed by disabling/enabling the adapter (incl. a computer restart).
Maybe it is worth mentioning that my router's Wi-Fi network uses WPA2 security protocol, while my ISP network does not use WPA2/WPA/WEP but does the authentication differently (PPPoE).
I hope this information helps with identifying the root cause. Please share your thoughts if you have any idea what may be going wrong.
01-10-2014 06:28 PM
Based on your original post, your other devices don't have problem. Based on this, I can assume it is not the router. If the router is the fault, all of your WLAN network will cease to function. It's a driver issue I think. One of the best way to confirm if is a driver issue is to stream 50 mp3s sequentially to 2 laptops at the same time from your desktop that is hardwired to modem/router . If at some point the Z510 experiences the issue that you originally posted while the other laptop continues to stream mp3s fine, then it's clearly a driver issue and you'll just wait for a new driver update that hopefully fixes the speed drop + packet loss issue.
01-23-2014 03:06 PM
For anyone still having troubles with the disconnecting, it seems like disabling HT mode for the wireless adapter solves the problem. From what I read, this essentially disables 802.11n and makes it work in 802.11g mode instead. The speed limit is supposed to be 57 Mbps although when using speedtest.net I get about 20 Mbps maximum, while at the time that 802.11n is working properly, I have been able to get to 37 Mbps. Seems like the router of my ISP that I was connecting to is using 802.11g standard. So far it has been working for nearly a week with no problems, although I have not tried 'breaking' it by starting/pausing downloads at high speed.
While this is not a real solution, at least it makes the laptop somewhat usable. I guess someone might find this information helpful.
01-26-2014 05:31 AM