HDD Failure

Gibbo58 · 9 Jun 2025 at 20:22

I'm currently using a 2013 21.5inch iMac booting windows 10 from an external SSD, crystaldiskmark reports the internal Apple HDD has a bad read error rate and that means it's on it's last leg. My question is when the internal HDD fails can I still boot from the external SSD via the boot menu or do I need to replace the HDD?

Rich (BB code):

IMG_8519 by Clive Viagas, on Flickr

JollyJamma · 15 Jun 2025 at 13:43

I’m no expert but I believe you can boot off the external drive.

You could upgrade/replace the internal drive but it’s difficult and a little pricey because you need the extra equipment.

You should try getting an external SSD enclosure with something like an SN850X 1tb and install OSX and if that doesn’t work, you’ve still got an external drive.

JollyJamma · 15 Jun 2025 at 13:45

Update: here is a guide. It’s not pricey since you don’t need the suction cups or anything extravagant but it does look a little fiddly

iMac Intel 21.5" EMC 2638 Hard Drive Replacement

Use this guide to replace or upgrade your hard drive.

www.ifixit.com

demonix · 15 Jun 2025 at 14:35

1321 reallocated sectors.

Back that hard drive up as it's only good for ewaste.