dvd drives can be attached externally. USB 3.0
Yup. That's how I do it.
Although this Pavilion desktop came with a DVD drive, it's one of these horrible, flimsy laptop-style ones, and I HATE it.
Just a few months prior to the old Compaq's demise, I'd outfitted it with a brand-new, internal 'tray-loader' from LiteOn. I've always preferred front-loaders, so; since on its own it actually looks quite neat & tidy - unlike some internal drives! - I bought a SATA-to-USB 3.0 adapter lead.
You have to make sure you buy the correct type here; some will work with an optical drive.....many won't. Those that do, although they basically use the same circuit board, there's one additional chip. And those that don't have this extra chip, can't communicate correctly with an optical drive for some reason.
You still need to plug in the supplied wall-wart these adapters come with, in order to supply enough power for the drive motor.
I stuck 4 domed, self-adhesive rubber 'feet' on the bottom of the unit - I keep a supply of these on hand - and it sits on top of the tower, happily functioning as an 'external' drive.
Works for me..!
Mike.