Anytime you think an update or other system change has negatively affected your OS you should first try a "System Restore" and restore to a point before the suspected change was made. System Restore will reverse driver
But also consider your router, modem, or ISP. Interference can affect wireless networks - like cordless phones, appliances, etc. Also try resetting your modem and/or router. Unplug the power from them for about 30 seconds, then power them back on. Can't hurt, might help.
Many times a wide area network slowdown is out "in the lines" and not on your local PC. These disruptions can take hours to days to correct depending on where you are.