I just bought a Lenovo IdeaPad Y500 with the Wireless-N 2230. Unfortunately, my internet speeds are repugnant when connected to wifi - around 2mbps down. Strangely, I still see the full 4mbps upload speed. My routers are a Linksys/Cisco WRT54GS2, and a new Apple Time Capsule. The problem exists on both of these routers. All of my other devices - 2 other laptops, iPhones, iPad, and any wired connections - all work fine on either router, and have full internet download speeds. The Time Capsule doesn't have QoS settings or an option to toggle WMM (as far as I can tell), and the issue exists when using the Linksys-Cisco router in a variety of states: WMM on/off, QoS on/off, Frame Burst on/off, etc. Both routers use WPA2 security. I'm using the latest wireless drivers. Any idea how to fix this problem?
There are different causes for this issue to happen. We recommend you to use WPA(2)-AES encryption. Please avoid TKIP or TKIP+AES option if possible; make sure both the router and the wireless profile in your computer are setup accordingly. The following article will provide further explanation on this subject:
Data rate will not exceed 54 Mbps when WEP or TKIP encryption is configured
Please note your Intel® Centrino Advanced-N 2230 wireless adapter operates at 2.4GHz. This means it may be subject to interference from other consumer wireless devices; sometimes changing the channel may help. You may also try other settings recommended settings in order to optimize the connection:
How to access and configure advanced Wi-Fi adapter settings
Possible interference by other wireless devices may impact 802.11n performance
You may also want to update the router's firmware.
I hope the suggestions help.