http://www.examiner.com/article/xbox...total-detailed
http://www.enstarz.com/articles/1163...conference.htm
According to a post from the NeoGAF video game forums, which translated the original source, the Xbox 720 will house an 8-core CPU, a customized AMD 8800 series GPU, and pack 8 GB of RAM – for comparison, the Nintendo Wii U has 2GB of RAM.
In addition to these technical details, the report also mentions that the Xbox 720 will use Windows 8 as an operating system and come with a 640 GB hard disk drive – the Xbox 360’s largest HDD currently is 320 GB.