No need to create partitions, the Windows 10 installer will do that for you, if needed. Just delete the current Windows partition after booting from your favorite partition manager (there are many free ones), and then install Windows 10 from the medium made by Microsofts Media Creation Tool in the empty space (I advice 128 GB at least).
In fact, you don't even need to delete anything. If you use a third party utility to mount the iso-file you download, you can run setup.exe from Windows 7, and it will install Windows 10, without even asking for a license code.
However, we really recommend to install Windows 10 on a new SSD, not on the old HDD. Much faster.
The OEM license code might not be valid on a new machine. Then you'll have to buy a new licence for the new machine.
Hello. I am currently upgrading my computer, i currently have original xps 420 dell, except that i have GTX 960 and new PSU, the windows 10 is OEM set on my motherboard. i have decided to make a new computer with completely new parts except the PSU and GPU and 2 500GB hard drives. because of this, i will need to reinstall windows 10 again on the new system with OEM key. my question comes to the hard drives. currently on the dell system, one of the drives have partition, separated in two and one of the partitions the windows has been installed on, while the other part is for my own use. the other hard drive hasnt been partitioned. i want to transfer my hard drives to the new build, with the un-partitioned drive to be left the same with the files, and the partitioned drive to have separate space where i can install the new windows on and other part for personal use just like i have now.
i have looked on YouTube showing that in order to bring my hard drives to new build i will have to uninstall my drives and separate the hard drives from my motherboard and then install them on new build, and other show how to create the partitions however its all confusing.
could anyone please help?!

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