For Steam Instructions see here.
The most common applications for PC Video Games are Valve's Steam and Electronic Art's (EAs) Origin. This guide goes through the backing up of their Game Installation Files onto an external hard drive which can be 10's-100's of GBs depending on the size of your game library and the subsequent reinstallation of the program and games without wasting time and bandwidth redownloading everything.
In brief we essentially copy our Games Installations Folder onto an external hard drive, reinstall the program on a new Windows Installation or transfer to a new computer and then use the program to search for the Game Installation Files and recreate the necessary links within the Windows Registry which allow you to play the games on the new Windows Installation.
I recommend a 2 TB External Hard Drive. These ones are powered solely by the USB.
USB Type C to USB 3.0 Connectors
If your computer is brand new and only has USB Type-C connectors then you may need a USB Type C to USB adaptor. I used these on my XPS 13 9365 (please use the affiliate links to help fund my guides).
2. Backing up Origin Game Installation Files "Origin Games"
If you can access your current installation, go to your Game Library. To the left your installed games will be shown lit up and the games which you own but have not installed will have a download icon on their bottom left hand corner. Before backing up your game installation files, right click the Origin icon on the notification tray and select Quit Origin:
Open two instances of Windows Explorer.
In the left we will open up the
Origin Games folder which contains the Steam Games Installation Files.
This is found in:
C:\Program Files (x86)\
If your current installation is working.
C:\Windows.old\Program Files (x86)\
If you have reinstalled Windows without wiping the drive.
In my case I do not have a Windows.old folder.
The folder you are interested in is the Origin Games folder:
It contains your Game Installation Files:
We can right click it and look at it's properties:
Mine is 44.4 GB:
I'll now copy it over to an external hard drive and leave a note in a notepad file saying it's located in C:\Program Files (x86)\
3. Reinstalling Stream and Recovering Steam Game Installation Files on a New Windows Installation
On your new computer or Clean Windows Installation. Install Origin and Log in as normal. All your games will show the Download Icon:
Go to the notification tray and quit EA Origin:
C:\Program Files (x86)\
Origin Games Folder from your External Hard Drive
When you launch EA Origin and try to install a game it will reinstall it from the files in the folder opposed to downloading every single file again: