PC Power Supplies (Part 3)

Last time i discussed many of the common connectors used on computer power supplies. You can read more here. I’ll try and finish here and discuss some of the new and innovative products that have become available to the modern pc builder.

One of the newest power connectors availble in new PCs is the SATA power connector. The Serial AT Attachment is a new standard developed in 2000 specifies new connectors and communication protocols for storage devices like Blue Ray/DVD and hard drives. The standard eliminates the large Parallel Ribbon cables or PATA (Parallel AT Attachment) connections. The AT is an old acronym from IBM that meant Advanced Technology but its was also copted like the term molex. The Serial ATA international organization (SATA-IO) was the organization responsible for the standardization of the connection. In addition to the smaller data connections the molex or (AMP Mate-N-Lok connector) was also replaced. You can read more about those connectors here. Also the new standard allowed for cool features like hot plugging, and AHCI or Advance Host Controller Interface and even and external version of the connection. I’ll talk more about those later. The new SATA power connector quickly became the de facto standard by 2008. Now its very difficult to find molex connectors on power supplies but there are adaptors you can use to convert from molex to SATA power or vice versa. The SATA power connections also come in Slimline and Micro variants that are even smaller the the original fifteen pin standard Power connectors. The SATA power connector is now the ubiquitous power connection for 5.25”, 3.5” , 2.5” device in modern PCs.

The enthusiast market has driven innovation in the power supply market, some of the innovation is useful some just cosmetic. One of the most useful features that have been developed is the “modular” power supply. When i started making PCs in the early 90’s power supplies would come with the 20/24 pin power connector the 4 pin cpu support and maybe 3-4 molex connections leaving the PSU. This meant this bulk that left the power supply and a good portion of the weight was this 4 inch bundle of multi color mass of cables. I remember often picking up power supplies by this huge mass of wires. That is a bad habit because it could ruin the solder joint inside the power supply but if you grabbed the whole trunk it was the bulk of the mass any way.These cable were often soldered onto the mainboard of the power supply and couldn’t be replace easily if a molex connector broke you’d have to re terminate that line or just replace it if you didn't have the pins or equipment needed. Also if you weren’t using all the cable it meant you’d have to tuck some in the case somewhere or it might hit a fan and cause distressing noises to the users. But now many power supply manufacturers offer modular power supplies that have terminations at the PSU’s case that you plug 2 ended cables into to power the PC components. This means that you can trim down the mass of cables that came out of the power supply and make the case much neater. Some modular power supplies just terminate the peripheral able and attach the motherboard connector soldered onto the PCB of the PSU. Usually the modular model of power supplies are only a bit more expensive than normal power supplies i recommend spending the extra 10-20 dollar to get one.