Mac Pro won’t load past login screen.

[mrk123]

If it's a 2011 MacBook Pro, it probably has a platter-based hard drive in it.

You can speed up the performance of the MBP by replacing it with an SSD.

ANYONE can do this. It's just a matter of removing the back cover (numerous screws, Phillips #00 drive required), changing drives, and then putting the back cover on again.

You'll also need a TORX T-6 driver to undo the "bosses" on the sides of the internal drive, and move them over to the SSD.

Best way to do it:
Buy a 2.5" SATA SSD. Don't buy "the fastest". Just "buy for price".
1tb or 512gb should do.

Buy a USB3 2.5" external enclosure, something like this:

SABRENT 2.5 Inch SATA to USB 3.0 Tool Free External Hard Drive Enclosure [Optimized for SSD, Support UASP SATA III] Black (EC-UASP)

SABRENT 2.5 Inch SATA to USB 3.0 Tool Free External Hard Drive Enclosure [Optimized for SSD, Support UASP SATA III] Black (EC-UASP)

www.amazon.com

Put the SSD into the enclosure.
Use disk utility to erase it to "Mac OS extended with journaling enabled, GUID partition format"

Now, use either CarbonCopyCloner or SuperDuper to clone the contents of the internal drive to the EXTERNAL SSD.

Now, DO A TEST BOOT TO MAKE SURE IT'S GOOD:
Reboot and hold down the OPTION key until the startup manager appears, then select the external SSD and see if it boots.

If you get a "good boot", NOW it's time to power down and "swap the drives".
Put the SSD into the MBP, and put the old drive into the enclosure.

Now, boot the MBP with the SSD inside (use the option key trick again).
Do you get a good boot?
If so, one more thing:
Go to the startup disk preference pane and set the SSD to be the new boot drive.
Then, reboot again, to check your results.

Everything look ok?
Now the old drive (in the enclosure) can become your "cloned backup".

Thanks. Solid advice.
Get this SSD external and get backed up then get the SSD internal. Will let you know how goes. A carbon back up of existing would be good as I have e all my programs and set up 👌🏽👌🏽