I upgraded my CPU and mobo recently from an AMD 6300 and an Asus board (cant remember what board specifically) to and I7 4790K and MSI Z87 Gaming mobo and my PC takes over 2 minutes to get into windows, sometimes it loads slightly faster, but the desktop will be black for about a minute before I can start any programs or do anything. Any ideas what could be causing this?
Also another thing, when I go to restart my PC it will power down, but not power up again, it sits in a kind of standby until it is switched off by holding in the power button.
What these guys said. You can't run the same Windows on a new chipset. Technically, sometimes you can, but it doesn't work optimally. You have to reinstall it.
Windows by default at OS installation will load drivers for the chipset and various components and store them in an optimal location. Installing the OS with your previous AMD chipset made windows optimize itself to that configuration. While using CCleaner or similar software to clean your machine, uninstalling AMD drivers and installing updated intel drivers would likely help. I am with the general consensus that you should reinstall the OS. It will eliminate problems that could and likely would arise down the road.