Because STM32F429 is not supported by Coocox CoIDE with all of its features, I downloaded CMSIS files for STM32F429 from ST’s web site, version 1.3.0. I created a new project for STM32F407 and replaced files with downloaded for STM32F429.
Now you can work with both discovery boards in Coocox, but I prefer working with Keil uVision (step-by-step tutorial for Keil uVision).
Also, Coocox does not support 2MB flash yet, only for 1MB, what is fixed in Keil.
All CMSIS files are in .rar file. You have to add them into project manually, do not use Coocox modules, because they don’t support F429. Project is already configured for 180MHz clock.
If you want to use Coocox with STM32F4 Discovery, then select STM32F407VG device in IDE when you create new project, or STM32F401RE for Nucleo F401-RE board.
You can also look at my step-by-step tutorial for Coocox on how to create new project, but only for STM32F407VF (STM32F4 Discovery) because STM32F429 is not supported yet in Coocox by default.