Question What should I do with new 4tb HDD?

Apr 17, 2019
I bought a new 4tb Hdd, forgot about MBR. It is cloned from the old MBR HDD by the techs who upgraded my computer. I am not booting from it. I dont think it is a good idea to convert to GPT, seems risky. I dont really want 2 HDDs in my system because of heat/power that an issue?

I originally wanted to replace my 5 yr old HDD. I have made a big mistake.
I am a newb. A newb mistake. I should have gone with a 2tb, cloned that and told the tech to make the new HDD the boot drive, I think.

-I could wipe it and have it as a GPT backup, but then my other drive is still 5 years old.
-I could rage quit and throw it in the trash
-I could use it as an external HDD? would that work?

Seems I will have to buy another 2tb HDD to replace my old HDD no matter what.