I'm having a problem with the Realtek RTL8723E like so many others, but in my case it simply refuses to connect. I am running Ubuntu 12.10 with the latest patches and kernel.
I referred to this excellent thread: Wireless card Realtek RTL8723AE-BT is not recognized to try to install the Realtek Wireless card on a new laptop - the Zoostorm W251EU. I have tried everything in the thread but the network manager simply shows 'Wireless networks' greyed out and disconnected.
Oddly enough this worked before on kernel 3.5.0-25 ... but after a reboot yesterday stopped working and has not worked since.
Hardware switch - works, and it is on
sudo lshw -C networkoutput
*-network description: Wireless interface product: Realtek Semiconductor Co., Ltd. vendor: Realtek Semiconductor Co., Ltd. physical id: 0 bus info: pci@0000:02:00.0 logical name: wlan0 version: 00 serial: 20:68:9d:dc:fe:25 width: 64 bits clock: 33MHz capabilities: pm msi pciexpress bus_master cap_list ethernet physical wireless configuration: broadcast=yes driver=rtl8723e driverversion=3.5.0-26-generic firmware=N/A latency=0 link=no multicast=yes wireless=IEEE 802.11bgn resources: irq:18 ioport:e000(size=256) memory:f7d00000-f7d03fff
rfkill listshows no hardware or software blocks
My blacklist is empty
rtl_92ce_92se_92de_8723ae_linux_mac80211_0007.0809.2012appears to make and install fine, but does not work any more. This worked previously with the 0-25 kernel (the problem appeared before the kernel upgrade to 0-26, I redid all the steps after installing kernel 0-26 in the hope it would start working again)
I'm running Windows 7 x64 inside VirtualBox, have tried to play with the network settings just in case there's some interference. No joy.