How to "Recover" windows from broken HDD

[DoctorPotato]

I built a computer in december 2014, and bought everything new, including an oem copy of windows 8.1. My computer worked alright, but after a few weeks, it would bluescreen almost everyday. I thought i was performing tasks that my computer couldnt handle, so i just dealt with it. Looking back, i realize it was probably my hard drive causing all these errors. Recently my hard drive will not boot windows. It will go into bios, but wont go into windows. At this point i am not interested in recovering the files of my hdd, but i am more interested in getting windows onto a new hard drive without repurchasing another copy of windows. I am aware that you cannot have two copies of windows running on two hdds. Any suggestions?
Edit: I have the windows 8.1 disk as well as the key

 

[popatim]

Sure you can, you just cant have two different pc's running windows.

Just use your dvd to install windows to the same pc as before. You will likely have to activate windows by phone because it will detect the change in hardware, but that will go fine as replacing the hdd is considered a repair and does not void the licensing.

its Changing the motherbd that causes big problems like that...