I have a modular computer power supply, and I needed an additional cable to run and additional card. Well I didn't have an extra cable, but what I did have is an older power supply that seemed to have the same connectors. So I plugged it in, and lo and behold it worked fine. But after doing some reading, it seems that people generally say this is a mistake. They say that it could fry components if you don't use a cable that came with the power supply or one you bought from the OEM. What I'd like to do, is understand why. I'm something of a newb when it comes to electricity. But to my mind, if the cable fits, it should work just fine.
You've got a connector, pins, and wires that connect to those pins. That's it. How can this result in frying anything? To me the only possible way, would be if you plugged it into the wrong port on the PSU. Since the ports on the PSU may be different, you might plug in a cable that does fit into the port, into the wrong port. And thus, supply too much power to the device. The only problem with that is, many power supplies are labeled. They'll tell you which ports are meant to power what. Its often printed right there on the power supply next to the ports. So if you had a cable from another PSU that fits, and you saw that it plugs into the port for a graphics card on the PSU, what could be the harm in that?
You've got a connector, pins, and wires that connect to those pins. That's it. How can this result in frying anything? To me the only possible way, would be if you plugged it into the wrong port on the PSU. Since the ports on the PSU may be different, you might plug in a cable that does fit into the port, into the wrong port. And thus, supply too much power to the device. The only problem with that is, many power supplies are labeled. They'll tell you which ports are meant to power what. Its often printed right there on the power supply next to the ports. So if you had a cable from another PSU that fits, and you saw that it plugs into the port for a graphics card on the PSU, what could be the harm in that?