04-29-2009 01:22 PM
I think this out and I'm guessing that on every sets of the drivers doing the same. I mean that when you set on max battery the drivers shout down WiFi connection and they suppose to fire it up, but they do not or do but not in normal time. On the other hand in max performance they work in this way but much faster. So when you use connection continuously the speed is dropping and rising. That's why you have got this problem.
So I do not know if it is drivers or it is wireless itself, but some thing is f... up. So my advise is to buy some new better card, I will do that as soon I get some money.
Ps. Do not get me start on behavior when it is connect in "N" mode.
12-12-2009 07:31 AM
Fixed this issue by disabling the wireless adapter's "802.11n Mode"!
I just got a new Thinkpad T400 with the Intel WiFi Link 5100 AGN card running Windows 7 Pro. Using http://www.speakeasy.net/speedtest/ as a guage of Internet peformance, I was getting ~700kpbs download. By comparison, I have also have a Thinkpad Z60t with Windows XP Pro getting wireless speeds of ~12,000kpbs.
I tried a variety of options, including updating drivers, disabling "Remote Differential Compression" --- none of these worked. What did work was disabling the wireless adapter's "802.11n Mode".
From 'Network Connections', right-click on 'properties'. Click the button to 'Configure..." the wireless adapter. Go to the 'Advanced' tab, which is the second tab after 'General'. In the 'Properties' box, the third option down for me is '802.11n Mode' which I set to 'disabled'. After rebooting, I was getting wireless speeds of ~12,000kpbs.
02-07-2010 01:07 PM
I had the same problem with my T400, and found that if I changed the 5th option Ad Hoc QoS Mode to WMM Disabled it allowed me to get the full throughput on my 802.11N and not have to drop to 802.11g as previsously stated. Seems that the QoS stuff causes alot of bursty performance issues.
12-03-2011 12:08 AM - edited 12-03-2011 01:47 AM
OMG!!!!! Thank you SO, SO much for this solution! I changed the 802.11n Mode = "Disabled" and it fixed my INCREDIBLY SLOW download speeds. I've spent 8 hrs on the phone with Lenovo... AFTER PAYING $89 TO EVEN TALK TO THEM!!!! And, they don't know about this solution. For now, I'll give up any extra speed n-mode might have given me. Before this fix, I had a very intermittent wireless connection that would occasional freeze for 20 seconds to 2 minutes! My download speed tests were running at 200-500 Kbps. As soon as I disabled 802.11N Mode, I jumped back up to 9-10 Mbps!!!! And, I no longer have the intermittent wireless freezes! Thank you! Thank you!!!!!!!
Lenovo wanted me to either send my laptop back (10 business day wait!!!) and/or re-install Window 7 (thus wiping out all of my weeks of installs on this new computer!!!) and I wasn't convinced that would even fix the problem. They were just grasping for a solution. I was about to buy a new Intel Centrino wireless 6150 N card and try installing the new hardware myself. But, I kept searching around and found your solution. It worked!!!!!
WHY DOESN'T LENOVO KNOW ABOUT THIS?!?!?!?!
THANK YOU AGAIN SO MUCH!
Details on this simple fix are: Open Control Panel, click on: Device Manager->Network Adapters->Intel Centrino Wireless N 6150 (or your card). Then, right-click and open Properties. Click Advanced tab. Then, click "802.11n Mode" and click "Disabled". Then, click "OK".
You saved me HUGE headaches by not having to return my computer or having to reinstall Windows!