I didn't uninstall older GPU drivers, and installed new drivers right away instead
 

I did this and then remembered that I had to uninstall GPU drivers first. I went to double check and sure enough I was supposed to uninstall old drivers first.

So, is this really harmful to my computer? Or can I fix this issue pretty easily? What do I do from here? Do I simply go and uninstall the drivers and then reinstall the latest drivers and that will work things out?

I'm a bit worried this problem won't be real easy to fix. : -\

I'm kind of new to PC gaming and before getting this PC I have now, on my old PC I never updated GPU drivers (I didn't game on it).

So long as you can see something on the screen, you're not in trouble.

Uninstall all GPU related software/drivers and restart. Then install the latest software/drivers and restart again.

Okay, good to hear. Thanks for the info on next steps.

It's safe and sound practice.

Should I find that the new nVidia drivers don't work for my game, I usually uninstall, reboot, and install the older version (285.58 was good for my GF6200 with temperature monitoring included, but got a BSOD while trying to load up my favorite MMO, so I downgraded back to 195.62).

Yeah, sometimes it's not worth updating drivers. I recommend doing a Google to make sure no one else is having trouble. It's not like Windows or Chrome where you need a security patch, after all.

I do believe Nvidia drivers have not required you to uninstall the older version for quite some time now- the newer installers automatically update your graphics drivers.

Do make sure you uninstall the drivers before you go installing a new GPU, though.

you should be fine imho, recent drivers has automatic uninstall sequenced to it right before installing the new drivers.
though from time to time some sh.tty error might occur and causing an unclean installation of the drivers, when this occurs theres two solution, booting in safe mode and cleaning up the f.ckd up drivers or re-installing the OS from scratch.