I recently bought a new 600w power supply and it says it has 100% full load burn-in. Can anyone tell me what this means?
Sure. It means your power supply, the one you have in your hands, has been operated on a load bank that draws the maximum rated power from the supply for a specific amount of time. It is similar to having an automobile engine run on a test stand at maximum design RPM for a specific amount of time. It is a good thing. Typically a sample of the production run is tested, perhaps 1 in 50, this way and all are plugged in for a few moments to make sure they operate and produce acceptable voltages but that test fails to isolate marginal components. The power supply normally won't be operated long enough for the whole power supply to get to full operating temperature. Temperature is what kills electronics. As components get hot their values change. That change is frequently in the direction that allows more current flow. More current means more heat and this vicious circle continues until something smokes and the supply stops working, best case, or it sets something on fire, worst case. The company that built your supply cared enough to test every supply it makes to the same degree as the cheaper companies test sample supplies. You shouldn't have any trouble with a unit tested this way. At least not for a long time. Congratulations, it sounds like you have an eye for the better stuff on the shelf.
