Fighting System Blackouts

It happens more often than many users realize. An old graphics card or a slow processor runs smoothly and without a peep for weeks, and then suddenly, after a system upgrade, system failures start occurring with nasty regularity. Frequently users blame problems like this on sloppily programmed drivers or hardware mined with errors.

But often it turns out that the power supply unit is simply no longer enough for the upgrade and the associated power requirements. The result is sporadic system failures due to unstable power delivery. Once it becomes clear that the DX9 capable AGP graphics card at full 3D capacity alone consumes up to 30 watts, the reaction is hardly surprising.

The CPU still requires the lion's share of electrical power: AMD's top model, for example, the Athlon64 3400+, allows itself over 100 watts on the power supply unit's 12-volt power bus alone when operating with a full load.

A capable, smoothly operating power supply unit is thus sorely needed, whether to satisfy the increased demand for processing power from an upgrade or because a deficient power supply unit needs to be replaced with a new one. If the voltages do not remain stable or exceed specifications, system components risk being damaged. Processors in particular react sensitively to instabilities in voltage.

In addition to stability, criteria for purchasing a power supply unit include operating noise and efficiency. First of all, the value of a stably operating power supply unit only lasts as long as it is guaranteed to go easy on the ears while doing its work. Moreover, more energy can be saved by avoiding unnecessary power use - for example, with a low-efficiency power supply unit. After all, the thing is supposed to guarantee a respectable power supply, not heat your apartment.

Following these criteria, THG has put fifteen power supply units of a nominal 300 to 550 watts to the test.