I have run into folk that call a PC Desktop POWER SUPPLY the "battery." But there is no "too powerful" in these units since the cards and boards in a desktop will consume what they need.
It's when the POWER SUPPLY is not powerful enough that you see the issues you described as the power supply drops out under the load. Hopefully it shuts down but some designs turn on/off or something else.
I'd go back to the setup that worked.
I recently purchased a new battery that was too powerful for my computer, after giving up on it I decided to reconnect my old one but now my desktop turns on and it seems everything's running, all the fans are spinning everything's making noise like you'd like it, all the lights are on but no video output? The gpu is getting power judging from its fan running smoothly so what's the deal? Did I **** it all up by trying a too powerful battery? Or what other things could it be?

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