power supply - Computer cables explained
2014-04
I've noticed lately that places to learn about both power supply cables and also peripherals and fans aren't that easy to find.
There's very little information available that gives detailed explanations of what cables are used inside a computer. What I found was very dated and often lacked detailed explanations.
For someone planning out their first build it would be great way for this to be explained all in one place, like here!
Important things to know about cables and connections in a computer?
What are their names?
Where do they connect to and why?
What typical Voltages do they output?
Changing Voltages for Overclocking?
Please refernce PSU cables(Full modular, Modular and Non-Modular,24-pin, 20+4-pin etc), SATA(I, II, III), Molex etc.
EDIT:
Forgot to mention any information about PSU rails would also be appreciated :)
MonkeyZeus
Unless you are trying to get your 24-pin motherboard to boot from a 20-pin power cable you really don't have much to worry about besides having the proper connector.
Available connectors off a PSU:
- 24-pin power cable for modern motherboards (~6 years old or newer)
- 4-pin and/or 8-pin auxiliary power for high-end motherboards that overclock like mad or simply a server-board that has to support a high-end and power-hungry CPU
- Sata power connector is used for hard drives, SSDs, and CD/DVD/Blu-Ray drives
- Old-style 4-hole molex used to be standard for HDDs, and CD/DVD drives
- Old-style Molex has many adapters if Sata power cables aren't plentiful in your build
- 6-pin and 8-pin PCI-e connectors are used for powering graphics cards which need more power than the 75-watt PCI-e 16x lane can provide on it's own.
- Do not confuse the PCI-e power with the auxiliary power connector mentioned in Bullet#2
- 3-pin fan power delivers a constant voltage (12-volts i think) so your fan speed is not adjustable
- 4-pin fan power allows you to control the fan speed either from the BIOS or within the OS so you can tell it to essentially do 5-volts, 7-volts, 9-volts, or max 12-volts which will in turn crank the RPM of the fan
- You can even get a fan controller which is a hub with a few 4-pin headers that is powered by Molex and software will allow you to control the speed of each individual header.
SATA data cable(s)
- The cable has not physically changed since the SATA I spec
- You can use a SATA cable from several years ago on a SATA III motherboard/SSD combo and achieve maximum speed. This is assuming that the cable was manufactured out of correct material in the first place such as copper and not tin
- Motherboards advertise SATA III because the speed spec has changed over time
I am sure there are many more things to talk about but this should get you going in the right direction.
The biggest thing to worry about is whether or not your PSU has enough AMPs to power the devices attached to that Rail. I personally use a PSU that delivers 40 amps on a single Rail, Corsair TX-750, so I don't worry about balancing Rails.
Read about PSU Rails and other goodness :)
Chenmunka
For the peripherals cabling, you will find most connections detailed on http://www.interfacebus.com/. It has some power standards too.
RainDoctor
What's the difference between a sata cable that does have a clip and one that does not have that clip?
The cable with a clip:
Satanicpuppy
Some people like clips, some people don't. If you have to move drives a lot, it helps make sure you don't accidentally pull the connection with the motherboard loose.
It's purely a matter of personal preference.
rob
There's no difference in terms of tech specs, but the cables without clips can come disconnected easily with the slightest bump when you're working inside the computer, even if you're not working on the disks.