You can leave it or remove it as you see fit.
Be sure you have tested that it boots from the SSD before you add the old drive.
Hi
I have installed a new SSD drive to my HP laptop to replace the original hard drive.
The original hard drive will be installed in a caddy in the DVD drive and used mainly for storing files
I have installed Windows 10 on my new SSD .
My question is , do I have to remove Windows from my original drive (being installed in DVD slot) which has files I still want to use on it?
Thanks in advance

Chowhound
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