How do you upgrade a power supply?

Answer

It is fairly easy to upgrade the power supply unit (PSU) of most recent desktop computers.

You'll need a screwdriver.

* Pop open the case of the computer and check the dimensions of the power supply in the case (or the empty space available if the old power supply has already been removed). Most of the time, you'll find a "ATX 2.0" power supply, also called "ATX with a 24 pin connector", 150 × 86 × 140 mm (5.9 × 3.4 × 5.5 in). I like to take a "before" photograph that shows how everything is connected.

* Obtain a new power supply. It needs to (a) fit in your case, (b) has the power rating you need, and ideally (c) has enough connectors for everything already in the box and also everything you plan on adding to the box.

* Unplug the computer from all power sources.

* Open the case, disconnect all the cables from the power supply to anything else, and take out all the screws holding the power supply in the case.

* Pull out the old power supply, insert the new power supply.

* Attach the new power supply to the case with the appropriate screws.

* Connect the power cables between the power supply and everything that needs power.

* This is where I review my "before" photograph, to make sure I didn't miss something.

* Close the case, and plug the computer into a UPS connected to mains power.

When adding more hard drives to a computer, or upgrading to a higher-powered graphics card, it may be necessary to upgrade the computer's power supply.

yes you can install a new power supply. but it wont affect performance what so ever

I disagree with the idea that upgrading a power supply doesn't improve performance. It does! Many video cards, hard drives, and assorted peripherals, over the years have had an increase in power consumption. The addition of powered USP ports has further taxed an older style power supply. The AGP architecture has reversed the power needs (4x to 8x) but with the addition of memory, and architectural differences on how memory uses power, the need for a higher wattage power supply is more conducive to a smoother running system. Further supporting this theory, you will find on the motherboard box or video card box, under "system requirements" they set a wattage requirement for the power supply in order to operate with out taxing the rest of the computer parts.