Ok, so I've searched high and low for a solution to this: An unknown directx error has occurred. please make sure your video card supports shader model 2.0 and that it is using drivers from the manufacture.
I've reinstalled directx, updated my graphics driver (not an issue with my graphics card unable to support LoL), I've disabled my anti-virus, I've closed any over-layed program (ex. vent, steam, mumble, skype, etc.), I've made sure all my service packs are up to date,I've repaired LoL, I've even ran other games to see if they work fine... In which, they do.
When I start a game, the "League of Legends" logo appears normally, everything seems to be fine, screen turns black (other than the logo), then begins to flash black and the window of black gets smaller, into the top left hand corner of my screen. The error window then pops up, relaying the message above. The only solution I have to this would be re-installing LoL, but I've read that still doesn't solve the problem.
League had been working fine for me in the previous days, except for yesterday when the problem occurred. After the patch, I was able to play league with minor lag issues (quite a few computers running on the internet here), but after that I'm unable to get into game. I'd think I could possible mess with the video settings if that's the problem, but I've been unable to find the config file in my folders.
If needed, I will provide dxdiag details.