Back up the original system before doing anything "mission critical" like a W10 upgrade. http://www.macrium.com/reflectfree.aspx is free and used by many people on this forum. Just remember to test your rescue media usb/cd after you've created it. Boot off it and make sure you can access your backup(s) then abort the programme.
Where you back up your system is up to the individual. I prefer another partition, external hdd, or networked NAS rather than a USB flash drive which can be fragile. You can never have too many backups.
Computer Type PC/Desktop System Manufacturer/Model Number Intel NUC D54250WYK OS Widows 10/Linux CPU i5 4250U Memory 4GB PC3-12800 Graphics Card Intel HD Graphics 5000 Monitor(s) Displays DELL U2412M Screen Resolution 1920x1200
Hard Drives PLEXTOR PX-256M5M mSATA. Internet Speed 100/15 Antivirus Nod32 Other Info +CM69O II, P8Z77-V PRO , i5-3570K @4.2Ghz
8GB Crucial 1866mhz, 850 Pro 256, Sandisk Extreme 256, WD 300GB, 600GB. GTX970
Computer Type PC/Desktop System Manufacturer/Model Number Home Brew OS 64-bit 10240 10 Pro CPU Intel Core i7 960 @3.20 GHz Motherboard MSI X-58 Pro-E MS7522 Memory 24.0 GB DDR3 Graphics Card EVGA GTX 750Ti Sound Card On Board Realtect 279 Monitor(s) Displays LG E2341 23 Inch Screen Resolution 1920X1080
Keyboard Logitech MK710 Mouse Logitech M705 PSU 750 Watt Case Haf 912 Cooling Corsair H-75 Hard Drives Samsung 250 gB SSD 850 EVO Internet Speed Cable Browser Firefox 42 Beta 5 Antivirus Avast Internet Security 10.4.2233
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