I upgraded to Windows 8 a couple of days ago, and to my dismay, League of Legends has constantly given me very large ping spikes (500+) about every 10 seconds which lasts for 2-3 seconds at a time. This results in my character being completely unresponsive during these times, and sometimes acting very strangely: sliding backwards, not casting skills, not attacking, or auto-attacking in excess.
In a couple of instances, this has been so bad that I have lost connection repeatedly during the whole duration of a game, which has cost me a ranked loss. I have confirmed that it is not my internet or computer, seeing as more demanding games run perfectly fine. I sometimes do not lag (about 1/5 games), and I sometimes have client crashes after pressing the victory/defeat button (about 1/8 games). I have also experienced lobby crashes today; twice during ranked queue's which resulted in 1:30 of temp ban.
I have tried reinstalling the game, running it using a different hard drive, updating drivers, turning off all non-essential processes, etc.
Nothing has worked consistently; this is quite frustrating for me, as you can imagine.

System Information:
OS: Windows 8 x64
CPU: i7 3770k @ 4.4GHz
GPU: HD 7850 x2 CrossfireX @ 950MHz/1350MHz
SSD: Samsung 840 250GB
HDD: Seagate Barracuda 1TB 7200RPM
RAM: GSkill Sniper 4x4GB @ 1866 9-10-9-28
Wireless Adapter: TL-WN722N w/ 7.5Mbps up 768Kbps down internet

I would like to note that I have had few issues with LoL prior to the Windows 8 upgrade, and the problem is exclusive to this game.
If anyone has a feasible solution to this problem please let me know.

If you have a static (permanent) IP address, make sure that the TCP/IP configuration for your ISP connection contains the correct information.

Follow these steps:
1.Connect to your ISP.
2.Start a command prompt, type the following command, ipconfig /all and then press ENTER:

This command displays all windows TCP/IP settings for all your network adapters and modem connections. The adress for your modem connection is displayed as "NDISWAN X Adapter" (The X is a number)
The default gateway for the NDISWAN x Adapter is the same as the ip adress, microsoft has repeatedly said this is by design.
Morre than one NDISWAN x adapter may be displayed. Any NDISWAN x adapters that are not currently in use display zeros for the IP address.

3.If the IP address that is displayed for your dial-up connection to your ISP does not match the IP address that your ISP gave you, change the IP address that is displayed so that it matches the address that your ISP gave you. Windows 8 has a fairly common bug in our work-place, that it changes thier IP adress.

Follow these steps: a.Click Start, point to Settings, click Control Panel, and then double-click Network Connections.
b.Right-click your Internet connection, click Properties, and then click the Networking tab.
c.Click the Internet Protocol adapter, and then click Properties.
d.If the settings are not correct, change the TCP/IP settings to match the settings provided by your ISP, click OK, and then click OK again.

If that doesnt fix your issue let me know. Its been fixing everyone elses internet issues.