any of these mobos fit my optiplex 780?

I would be careful with that swap. The 980 is kind of a unicorn. It's a BTX layout but not LGA775/771 which BTX came and went with. The 980 uses it's own cooling solution and I think the bolt pattern may be different. This is important on a Dell Optiplex because it bolts into the case directly, not to the MB or a backplate, or even removeable risers.. The classic BTX has the CPU turned 45* like the 780 does.
A built Opti 780 would have a Q9650,16GB DDR3 1066 RAM, and a Zotac GTX1050Ti Mini. A bigger GPU will require modding and a PSU upgrade.
If you need more than that I would suggest another computer. The Opti 780 was end of the line for Optiplex BTX layout.

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