Comment 116 for bug 1049466

Found another possible workaround if you want to use vendor's proprietary drivers. Someone over at archlinux created a patch for mediatek's driver: https://aur.archlinux.org/packages/rt3290sta-dkms/?setlang=ru

Original Driver: http://www.mediatek.com/_en/07_downloads/01-1_windowsDetail.php?sn=5033
Patch: https://www.dropbox.com/s/v0kaibq0f4to0k2/rt3290sta.patch

I wrapped it up into DKMS so it can easily get rebuilt on kernel upgrades. Download and untar into /usr/src and then run:

dkms install -m rt3290sta -v 2.6.0.0
modprobe rt3290sta

This will:
1 - Add it to DKMS tree
2 - Build the rt3290sta driver with the patch
2 - Install it to the kernel driver tree
3 - Blacklist original kernel drivers rt2x00pci & rt2800pci from loading by creating /etc/modprobe.d/blacklist-ralink.conf

To remove:
dkms remove t3290sta/2.6.0.0 -all