Cables & Adapters
Overclockers UK stocks a wide range of cables including a variety of Multimedia display cables such as HDMI, DVI,VGA and DisplayPort cables. In addition to this we sell many different external and internal cables from Kettle leads to SATA cables. No matter if you are building a PC or just trying to plug it into your network, we have the cable you need.
Cables
A cable is a fairly simple device allowing for the transfer of data and/or ‘power’ via 1 of 2 methods:
Electrical: Electrical cable is an assembly of 1 or more wires, designed to carry electrical current and/or electrical signals. Electrical cables are normally made of either a solid or woven core of copper and covered with a fire resistant and electrically insulating plastic such as PVC. Depending on the purpose of the cabling certain cables are also shielded from electromagnetic interference.
Fibre Optic: Although externally similar to an electrical cable, they contain one or more optical fibers that carry light which is encoded with data. These cables literally allow data to transfer at the speed of light which is why they are used for high speed applications such as fibre broadband and audio.
Multimedia cable overview
VGA
Video Graphics Array (VGA) is one of the very original display connectors and introduced by IBM in 1987. It remained the golden standard for years and is still present on low end hardware. As VGA utilises an analogue signal it has to be converted which is known to degrade the quality. VGA cables are also susceptible to cross talk and noise so it’s paramount to use thick VGA cables that insulate the signal. Although an older platform, VGA can still support a resolution upto 2048x1535 at 85Hz.
DVI
Digital Visual Interface (DVI) is a video interface designed to allow the transfer of uncompressed video content. Developed by the Digital Display Working Group and launched in 1999. The interface Supports a maximum resolution of 2560x1600 and multiple modes including:
> DVI-A (analogue only) 1920x1600 @ 60Hz
DVI-A is an analogue only signal. The 4 pins surrounding the blade essentially act as individual colour channels – Red, Green and Blue (RGB) with the final pin acting as a ground. You can convert DVI-A to a VGA connection utilising a DVI to VGA adaptor or cable.
> DVI-D (digital only) single 1920x1600 @ 60Hz / Dual 2560x1600 @ 60Hz
DVI-D is a digital only signal and missing the analogue pins completely. Single link DVI supports a max bandwidth of 165MHz and a maximum resolution of 1920 x 1080 at 60 Hz. Dual link on the other hand supports 2x 165 MHz at a resolution of 2048 x 1536 at 60 Hz.
> DVI-I (digital and analogue) single/dual link
DVI-I is simply a combination of DVI-A and DVI-D allowing either analogue or digital.
HDMI
High Definition Multimedia Interface (HDMI) is a proprietary interface for transmitting uncompressed audio or video data from a HDMI compliant device to a display such as a monitor or TV. Designed in 2002 by multiple collaborator’s including Hitachi, Panasonic, Philips, Sony, Toshiba and many others. The interface has been cemented as the market leader thanks to its mass adoption in everyday technology. The wide variety of sized connectors and its ability to support resolutions upto 7680 x 4320.
Connectors
There are 5 specific HDMI connectors from A-E using a variety of specifications
HDMI Specifications
| 1.0-1.2a | 1.3-1.3a | 1.4-14b | 2.0-2.0b | 2.1 | |
|---|---|---|---|---|---|
| Transmission Bandwidth | 4.95 Gbit/s | 10.2 Gbit/s | 10.2 | 18 Gbit/s | 48 Gbit/s |
| Maximum Date Rate | 3.96 Gbit/s | 8.16 Gbit/s | 8.16 Gbit/s | 14.4 Gbit/s | 42.6 Gbit/s |
| Maximum Character Rate | 165 MHz | 340 MHz | 340 MHz | 600 MHz | 1.2GHz |
| Data Channels | 3 | 3 | 3 | 3 | 4 |
| Encoding Scheme | 8b/10b | 8b/10b | 8b/10b | 8b/10b | 16b/18b |
DisplayPort
DisplayPort was developed by a consortium of PC component manufacturers and launched in 2008. Designed to replace VGA and DVI and backwards compatible with other digital formats. DisplayPort support a resolution upto 7680x4320 at 60Hz which means the format is on par with HDMI but with one large difference.
Unlike other digital formats DisplayPort utilise a packet data transmission system which is found in other technologies such as Ethernet and PCIE. Essentially the technology embeds micro packets into the data stream which allows for a higher resolution using fewer pins. This also means the technology can be upgraded in the future so additional features can be added. Currently the interface is capable of not only carrying audio and video but bi directional USB signals. As with HDMI there are many different versions:
DisplayPort Specifications
| 1.0-1.1a | 1.2-1.2a | 1.3 | |
|---|---|---|---|
| Max Resolution | 3840 x 2160 (4K) | 3840 x 2160 (4K) | 7680 x 4320 (8K) |
| Multi Stream Transport | No | Yes | Yes |
| 3D | Limited | Yes | Yes |
| Video Compression | No | No | Yes |
| Audio | Yes | Yes | Yes |
| HD Audio | No | Yes | Yes |
| HDCP Version | 1.x | 1.x | 1.x / 2.2 |
Audio cable overview
There are 2 main types of audio cables used with computers today, the 3.5mm AUX and the Optical. Let’s take a look at the 2 formats….
3.5mm AUX
Originally conceived as a two-conductor connector for transistor radio earpieces in the 1950’s and popularised by the Sony EFM-117J radio. Most portable technology such as mobile phone and computer front panel computer audio connectors still use the standard 3.5mm audio interface, providing stereo sound to headphones or stereo speakers.
Optical
Optical cables utilise fiber optic technology to transfer sound from a device such as a PC to a optical decoder that is usually built into an amplifier which converts the light into multiple channels of sound allowing for upto 7.1 channels of sound output creating a rich, well rounded audio experience.
Optical cable’s enable users to separate audio channels from the video output connection, allowing for precise control over the audio signal. Unlike the standard AUX (Headphone jack) connection, optical is able to carry upto 7.1 surround sound audio.
Adapters
Adaptors are designed to allow you to convert one format to another. When it comes to Multimedia cables in particular, adaptors can be very useful. Very rarely will you find multiple HDMI connections for instance on a graphics card so you might need to convert DVI or a DisplayPort instead if using a multi monitor setup.
Do I need a Passive or Active adaptors?
This depends on if you need to convert from one format to another and what resolution you want to achieve. 9 times out of 10 a passive adaptor will be more than sufficient but in certain circumstances an active adaptor will be required.
> Passive
Passive adaptors are relatively cheap and do not include any additional circuits. This means they rely on the systems internal hardware to detect the monitor and output the correct signal.
> Active
Active adaptors on the other hand utilise an internal chip that converts a signal to the desired output type and are required for certain resolutions. Active adaptors can additionally fool the computers GPU into believing it’s outputting to DVI and then converting to the required signal type.
