7. Install the fan. You may forget to put back or install new hardwares but you should never forget installing the fan power. Yes, you will be able to turn on your computer, but after few minutes, you will notice that your computer is producing quite an odd sound. A minute or so will pass and it shuts down. Congratulations, your computer just overheated. So, to prevent this, never forget to install the fan power.
8. Minimal installation at first. If you are trying to install an operating system, you might want to install the basics first such as memory cards, fan power, power supply and CD-ROM. With these, you may be able to setup your computer. You may add on the additional frills of your computer once setup is done.
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