@mcc 750W should be fine unless if you have one GPU. Unless you have an RTXxx90, sound like you are good on that side.

An easy way to check if your setup use too much power would be to downclock it. Power usage increase at a square of the clock frequency so reducing clock speed by 10% nearly reduce power usage by 20%.

@mcc I mess up that tweet beginning.

one gpu up to 3080/4080: fine
one 3090/4090: should be ok
two gpu: I hope they are small ones