I remember it wasn't too long ago when the cases we purchased had serviceable power supplies included, and not a whole lot of thought was put into that crucial component of our computers. However, back then the power requirements for our PCs were a fraction of what they are today. With current processors drawing prodigious amounts of power, and high end video cards not too far behind, a weak power supply can spell disaster not only in stability of a PC, but ultimately can put at risk the very components we prize so. If anyone has ever had a power supply die, it can be a pretty unpleasant situation, and can cause damage to various parts including motherboard, CPU, video card, and hard drives to name just a few. I learned long ago to invest wisely in a good quality power supply.
Power supplies can die for a variety of reasons. Foremost among those reasons is cheap construction and overloading. While power supplies are rated to deliver a certain amount of operating amps of current at 3.3v, 5v, and 12v power lines; in cheaper units this rating is somewhat of wishful thinking on the part of the manufacturer. A common way to obtain a higher rating than the power supply would otherwise achieve is to rate the power delivery during operation in low ambient temperatures. That might be fine if you leave your computer outdoors in the middle of winter where temps approach 10°C or lower; however those of us in the real world will be exposed to much higher temps and herein lays the problem. As heat increases, so does electrical resistance and consequently power delivery of the power supply suffers to a point. Manufacturers of higher quality units are more apt to rate their units at true ambient and realistic operating temperatures giving the enthusiast a true glimpse as to the capability of the unit, and not a fractured truth on which to possibly endanger their computer components.
Another area where high quality power supplies dwarf their cheaper counterparts is in power fluctuations or hopefully a minimum thereof. Voltage "ripple" which are sort of like peaks and valleys can cause problems in both stability of our computers and potentially harmful effects from such vacillation. Higher quality units are build to hold more consistent lines of power and minimize voltage ripple.
Today we are looking at 3 new units that are of high quality and conform to the new extended ATX standard with 24 pin ATX headers, SATA power cables, and PCI Express video card power plugs. Intel Socket 775 platforms based on the 915/925 series chipsets and newer AMD PCI Express motherboards are supporting newer ATX extended power supplies meaning they will accept a 24 pin ATX header for improved power delivery.
While it's possible to use an older ATX power supply with these newer boards, there are user reports of a potential drop-off in the ability of these older units to deliver clean and efficient power at top overclock. Since we often push our computers past their limits in our dark and damp dungeons here at Madshrimps; Zippy
felt such torture would be a good test for their new PCI Express ready power supplies. These units are of supposed high quality, but when stressed with highly overclocked CPUs how will they perform? Today we will turn up power demands on these fine units in an effort to find their strengths and weaknesses.