Windows 10: Can’t get my new SSD to be main Boot drive

So after someone told me I should make my SSD the new main thing to boot from as it makes everything faster, I listened and followed tutorials. I created the Installation Media on a USB, installed it onto the SSD which looks like it’s registered fine in the device manager and then went to use it as the main boot priority but it literally didn’t do anything. I just got a black screen with a flashing underscore at the top left, and then after a while it took me to Windows Install, which I’d already done on that drive earlier just fine. I did manage to load in briefly after the installation and

:)

 

New SSD wont boot

Hi John

Boot into BIOS, is SATA Mode set to AHCI to enable booting from an SSD drive?

Is the SSD drive set a top of the Boot Priority list?

Did you try connecting that SSD to the SATA Port normally used by your old HDD?

 

New windows 10 installtion on New SSD - wont boot unless old SSD present

It seems you installed Windows while the both SSDs were connected. This would have caused your current problem. Maybe it is sufficient to do this:

1. Launch the Disk Manager.
2. Right-click drive C:, then mark it as "active".
3. Shut down Windows
4. Open the BIOS and tell it that the new SSD is the primary boot device.
5. Disconnect the old SSD.
6. Boot up normally.

If this does not work then you might have to do this:

1. Disconnect the old SSD.
2. Re-install Windows on the new SSD, using the Media Creation Tool.

 

Can't boot from new drive

Thanks for the reply, but I'm not following you...

• What are you suggesting I unplug? Other USB devices? Done, but made no difference. (Ethernet? Monitors? Don't think that'll help.)
  
• Not sure I understand your partitioning advice?
  
• Also unclear about SSD drivers; if there was a driver issue, wouldn't it had failed to work at all? (As mentioned, I am able to boot Windows from the new drive as long as the old one is still plugged in...and it works just fine as a secondary drive.)