The system requirements for League of legends has not been finalized, nor will it be finalized until it is about to release. Below is a list of requirements that I have compiled based on post in the forums.
This a minimum recommended. It may run on less, but it is not advised
XP Service Pack 3
Vista Service Pack 1
CPU 2 GHz CPU
RAM 1024 meg memory
Hard Drive approximately 1.3 gig of hard drive space
Video Card must support shader model 2.0
- nvidia: GeForce 5 or better
- ati: any 9xxx after and not including the 9250, any Xxxx after and including the X300
- intel: no clue, if you have an idea let me know
Video card memory recommended minimum is 512 meg at the moment
Internet connection required at all times currently, Dial-up will not work currently
SLI is not currently supported. Some users have had no reported issue. Others have reported anomalies and sometimes crashes.
Crossfire works, but I do not know if it is officially supported at this time. Personally I run it and have had no problems.
To even consider doing this your machine MUST SUPPORT bootcamp. Using any form of virtualization will not work
Bootcamp Link: https://www.apple.com/support/bootcamp/getstarted/
Attempts have been made to get it to work in WINE but I believe it currently does not work because of a problem with scrolling on one of the agreements. If I understood correctly its a known problem with WINE. However I have not kept up with all of the post so I recommend you do some searching within the forums.
Download Link: https://www.winehq.org/
LOL Free download link