How to Install a New Power Supply in an ATX Case
- 1). Power down your computer and unplug the black power cord. Unscrew the thumb screws or fastening screws on the case with a Phillips screwdriver and open the case.
- 2). Unscrew the mounting screws holding the old power supply in place. Sketch a layout of the cables and what they connect to inside your computer. The more detailed your sketch, the easier it will be to reconnect the new power supply's cables.
- 3). Remove the old power supply and detach the cables from each of its connections.
- 4). Place the new power supply inside the case in the old power supply's location. Secure the new power supply with mounting screws and the Phillips screwdriver.
- 5). Connect the cables to the correct connections according to the sketch you drew in Step 2. Seat the connections securely. You will have cables for your motherboard, hard drive, CD-ROM drive and other components of your system. Tuck the extra cables you don't have a need for at this time neatly into the case of your computer. If you add additional hard drives or other components, you will need these cables.
- 6). Secure the case with the screws you took off when you opened it. Plug in the power cable and power up your computer. Your new power supply is now supplying the power to your computer.
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