I have dell Inspiron 3521 laptop and the original hard drive is busy failing so I bought a replacement, my laptop has windows 8 pre installed but it was upgraded for free to windows 8.1 so my question is, after I replace the hard drive, how do I reinstall windows 8.1? Or will the laptop do that on its own? And after windows is installed, do I need to download the Dell drivers?
The simplest way would be to clone your old hard drive to your new hard drive/SSD https://www.youtube.com/watch?v=LClr3FPg4_4
I would run disk check on your old hard drive and install the Macrium Reflect software and create your Recovery USB thumb drive. connect your new Hard drive/SSD and boot up using your Recovery USB that will put you in Windows PE mode. If your hard drive has not completely failed this will work.
Notice I said hard drive/SSD, SSDs are so much better than hard drives and almost as cheap nowadays you should consider one since you have to replace your hard drive anyway.
If you have to clean install, yes you'll need to download hardware drivers and Dell software. You can get an install media to download https://www.microsoft.com/en-us/software-download/windows8ISO
Since you have previously had 8.1 installed it should automatically recognize your hardware. You may have a copy of your product ID somewhere? during install, if it asks for a product ID you can just skip or put in Your 8 product ID or just put in a generic key. I'm trying to remember exactly how to install 8 or 8.1 pretty sure you don't need it since your hardware already had it. MS Activation Servers will see that at activation time.
All in all, is much easier to clone than to reinstall
ive already purchased a new HDD, same brand as the one that came with the laptop, same size storage wise but a different model. I didnt get an SSD because ive read too many conflicting things about how this particular model laptop may not even support it. So in the end i decided not to risk it. What i've done so far is download the windows 8.1 iso and created a bootable USB using rufus. So -hopefully- it will automatically activate after i install it. I looked at the cloning option, but im not concerned about losing data since most if not all was saved to an external hard drive months in advance
The point is clone takes 20 minutes, Clean install could take you days of work to get all your drivers and software working again.
Fortunately, I don't have a lot of software to install. I'm pretty sure if I were to clone, I'd be cloning the errors off the old hard drive, wouldn't I? Or there'd be a risk of it happening if there are errors that can be cloned. I'd rather start off fresh. Thanks for the help though.
Up until recently, Windows offered a free upgrade to Windows 10 to Windows 7, 8 & 8.1 users.
I'd suggest you download the iso file of Windows from the Offical website of Microsoft and install it.
Then you could install all the hardware drivers you need for your laptop after downloading them from the official website of Dell.
This is the official website of Microsoft that offers a tool to create a bootable USB to install Windows on your system
I hope this helps!