Hi, I have Intel centrino Ultimate-N 6300 wireless card, but it works only 54Mbps speed, Drivers are latest from intel support site, in device manager I see only a/b/g mode. Where is wireless N mode gone? I update drivers, configure my router: (Linksys E1000) if I leave only N mode, I cannot connect to router at all with wireless...
Somebody can help me? 
There is an 802.11n mode option
Intel got some info regarding the connection
Ensure you are using WPA2-PSK and AES encryption on your router... that worked for me.
Does your router support 802.11N mode?
Here is a configuration pic of Linksys E1000.
But I guess you have put both the wireless adapter and the router to work under 40MHz or auto mode.
This option I set to Auto. I try 40, but nothing
I have DD-WRT software on this router.
There would not be a/b/g/n mode available in Device Manager (maybe due to the setting UI from Intel), but when you set to a/b/g mode, the adapter actually could reach up to 300Mbs. Just make sure the 802.11n mode is enble.
But after enabling the 802.11n mode, you need check the 2.4GHz 802.11n channel width, change the default 20MHz to auto, then the adapter would switch to 40MHz and enable the channel bonding. This time, if the adapter connect to a router supporting 802.11n mode, supporting 2.4GHz 802.11n channel width swithing (that's the 20MHz or auto setting in your router), you can see the speed of the connection becomes 300Mbs.
If 2.4GHz 802.11n channel width is set to 20MHz, the top speed would go to 150Mbs at most. So, you need to check this.
40MHz means channel bonding in 2.4GHz 802.11n, when both the wireless adapter and the router supports, the connection could get 300Mbs.
Maybe you have noticed these.
As Peter mentioned above, the WPA encryption would limit the speed at 54Mbs, so you need to check this too. Make sure the connection is using WPA2-PSK and AES encryption, or without encryption.
You have powerful wireless card and router, just check those settings.
I'm using an Intel 6230GN wireless card. The setting UI is exactly the same with yours. It works fine with my bargin router, but now I got a problem, everyday around 9:20 am, the card would stop working. At first, the connection showed limited connection, then when I click disconnect, the adapter just disappeared, both from Network and Sharing Centre, and Device Manager. Worse thing hanppened, even the wired adapter couldn't be enabled. Device Manager just died, it would not scan for new hardware. The most terrible thing was you couldn't shut down the computer.
When the Intel 6230GN wireless card is normal, there is still a strange thing. When I change 20MHz to auto of 2.4GHz 802.11n channel width setting in Device Manager, the wireless card adapter would disappear for a while, and comes up until I click the Scan for new hardware.
broliukaz, If you change 2.4GHz 802.11n channel width setting from 20MHz to auto or from auto to 20MHz in Device Manager, would this happen too?
Looking forward to you reply.
Thx！
Here is my router settings:
http://es.too.lt/wireless1.jpg
http://es.too.lt/wireless2.jpg
Here is my computer wireless card settings:
http://es.too.lt/wireless4.jpg
here is the problem:
Sorry, some link is broken, here is working:
Here is my router settings:
http://es.too.lt/wireless1.jpg
http://es.too.lt/wireless2.jpg
Here is my computer wireless card settings:
http://es.too.lt/wireless4.jpg
here is the problem:
How is the speed showed in Windows Task Manager? Got a pic?
