technical terms
12V rails
The 12V rails on a power supply are marked by a yellow wire. 12V (DC) has developed over the years into the most important supply voltage within a computer and delivers power primarily to the graphic card(s), processor and (optical) drives.
20/24 pin (ATX connector)
The 20/24 pin connector – also known as the ATX plug – is the biggest and also the most important plug for a power supply unit. It is connected to the mainboard and delivers not only the three primary power voltages (3.3V, 5V and 12V) but also the power-good signal required for operation as well as 5V stand-by and -12V. The 20/24 pin connector is thus a computer's primary power supply connection.
4+4 pin (connector)
The 4+4 pin plug is also known as the 8-pin EPS connector. It contains eight cables, including four connected to the 12V rail. The other four cables connect the power supply to the earth. This plug delivers power to modern multi-core processors. The 4+4 pin is also informally known as the 8 pin connector or p8 plug.
Ampere (A)
Electrical current is measured in ampere, which describes the movement of electrons in an electric circuit. The abbreviation for ampere is a capital A.
Air Flow
The air flow indicates how much air a fan can move per unit of time. Because the air being moved represents a volume, air flow is indicated in cubic meters per hour (m3/h), or CFM. Among other factors, air flow reflects the number of fan blades, their operating angle and rotational speed.
AC (Output)
The acronym stands for "Alternating Current". It refers to the fact that the electricity periodically switches its polarity in even portions. The most common form of AC is sinusoidal.
All In One Cable
Various power supply series are equipped with a cable bundle containing all drive connectors. Each cable bundle thus contains at least one Molex plug, one S-ATA plug and one floppy plug. The benefit is that only one single cable bundle need be installed to power all of the drives used in a computer.
Continuous Output (effective)
In counterpoint to a temporary output (peak), the continuous output describes the performance of an electricity source that is issued continuously and without a time restriction. The continuous output is one of the general terms associated with power and hence is indicated in watts.
CrossFire
CrossFire refers to a function in which multiple graphics cards are operated within one computer. The technology comes from AMD and is the equivalent to NVIDIA's SLI technology. Operating two graphics cards in a CrossFire configuration provides greater graphics card performance for the computer. All current dual GPU graphics cards from AMD are based internally on CrossFire.
Combined Power
Combined power refers to the max. (combined) power that for example the 3.3V and 5V rails can achieve together at the same time. This applies to the 12V rails as well if these are divided into several individual rails.