Ok so here is the
issue.
I found the motherboard, and it
does have the right connectors, but there are many Optiplex 780 motherboards that don't have the right connector. So the only way to tell is you need to open your computer and look for a socket.
The connector you are looking for is called a "
PCI-E x16"
(Pretty much any x16 socket)
Here is what to look for
Common sockets
More common connectors
PCI-E 1.0 x16 (The yellow one)
PCI-E 2.0 x16
PCI-E 3.0 x16
Make sure to see what version you have too
(1.0, 2.0, 3.0).
If you don't have the right socket, then makes sure to just look at all of them and make a list. That will help me out.
And if you do have the right connector, there are still more issues.
Let me explain.
This is a like a 8 year old machine, and the CPU is outdated. And if you put new modern GPU in the system, the CPU isn't going to be fast enough to keep up. This is called
bottlenecking. So pretty much, the CPU and GPU are doing their job, but then the GPU gets done before the CPU. So then the GPU will have to wait for the CPU, which slows down the computer, and gives you a lot less FPS in games. The computer can only be as good as the processor.
Bottlenecking can be with anything. The RAM, like if you only have 2Gb of ram. Or the HDD, if its like broken and really slow. But I can tell that this CPU is going to be a bottleneck with these GPUs that I have listed.
So find out what socket you have, then I can help you from there.