Why is it important to buy a power supply that's close to the requirements for your system instead of buying a higher wattage power supply?

Answer 1

It's not. A higher than needed power supply will not harm your computer in any way. It will simply cost slightly more and draw more power. As they are more expensive, higher-watt power supplies will often have better warranties. A higher wattage will also facilitate future expansion more easily, instead of you needing to purchase a larger one later anyway.

Answer 2

It's not. The only thing you'll save by buying the one with lower-rated wattage is a couple cents of electricity a month.
I believe you have that backwards. There is no such thing as too much because the computer only takes what it needs. But there such a thing as not enough power that can cause many problems including hardware failure.

Answer 3

To little voltage and you will be receiving BSOD's all the time as when one device draws a lot of power (graphics cards) it will suck away electricity from other devices, Now as far as to much the only downsides are cost and heat production, If you have a 1kw power supply but only need 300 watts, then you are paying 700 watts an hour extra on your electric bill, and the heat generated from a large power supply can heat up a computer case a great deal.

Answer 4

The Power supply gives power to your motherboard, which gives power to all the components in your computer. If you put in a PSU with a higher Wattage, you could potentially overload the motherboard causing it to not work anymore. Stick to what's close to the requirements, and this issue will not arise.