The power supply is the single most critical component in the entire system. A faulty unit can die a horrible death, taking out several key components in the process, while an underpowered part can cause crashes or even boot failure. Since low-quality parts often fail to live up to specifications, we'll start off with links to our power supply stress tests, Part 1 and Part 2.

How large does a power supply typically need to be? The greatest determining factor in gaming systems will be the graphics card, but CPU power takes priority in integrated-graphics office systems. Several power supply calculators are available on the web - some more up-to-date than others.

While simple power supply calculators will often do the job for simple systems, the highest-end graphics cards place higher load bias on 12V rails. ATI and nVidia have taken this into account and published Crossfire Certified and SLI Certified power supply lists that are specific for each card.

For detailed information on additional power supply models, check out our cooling and power supply reviews.

Other Components

A system is never complete without an optical drive, and a recent transition to 18x DVD write speeds has brought forth a great number of new products. Even the most tight-fisted builder should be able to afford a DVD writer. Of course, buying from a respected vender will help you to avoid frustration should the new model turn out to be a dud.

A few system builders still want a floppy drive, and these are available for a nominal price, even from respected brand names such as Mitsumi, Panasonic, Sony and Teac. Also in the "rarely wanted" category these days are analogue modems.

Conclusion

With the daunting task of general selection guidelines complete, we look forward to our next segment: choosing the right vendor.