You probably don’t even need 750W but that’s probably the high end of what you want. I would hold off on CPU until next month. AMD (intel’s competitor) is showing off their new CPU and GPU. Their CPUs have been really getting at Intel lately, and they are a lot more friendly to upgrade. Their chip sockets for the CPUs tend to last longer. Also, idk how much you kept up with 3080 stock, but you gonna either be camping out online or potentially waiting a cool minute. That’s what I’m upgrading to when stock is readily available, but it’s looking spooky.
All in all you will probably get a better cheaper computer by waiting a few wks+, and you’re definitely not gonna have a good time hunting down that 3080
Also, make sure you or your homeboy are comfortable with liquid cooling and overclocking because that requires a little bit of maintenance.
All my opinion tho take it with a grain of salt