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The VESA Local Bus was designed as a stopgap solution to the problem of the ISA bus's limited bandwidth.
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VESA and Local
By the time there was a strong market need for a bus of these speeds and capabilities, the VESA Local Bus and later PCI filled this niche and EISA vanished into obscurity.
For general desktop computer use it has been supplanted by later buses such as IBM Micro Channel, VESA Local Bus, Peripheral Component Interconnect and other successors.
The PCI Local Bus was first implemented in IBM PC compatibles, where it displaced the combination of ISA plus one VESA Local Bus as the bus configuration.
VESA ( Video Electronics Standards Association ) Local Bus worked alongside the ISA bus ; it acted as a high-speed conduit for memory-mapped I / O and DMA, while the ISA bus handled interrupts and port-mapped I / O.
When the Pentium processor arrived there were major differences in its bus design, and was not easily adaptable to a VESA Local Bus implementation.
Most PCs that used VESA Local Bus had only one or two VLB capable ISA slots from the 5 or 6 available ( thus 4 ISA slots generally were just that, ISA only ).
Despite these problems, the VESA Local Bus became very commonplace on later 486 motherboards, with a majority of later ( post 1993 ) 486-based systems featuring a VESA Local Bus video card.
PCI also displaced the VESA Local Bus in the remaining 486 market, with some of the last 80486 motherboards featuring PCI slots instead of VLB slots.
Compaq ) and then the VESA Local Bus Standard, were late 1980s expansion buses that were tied but not exclusive to the 80386 and 80486 CPU bus.
The PC clone market did not want to pay royalties to IBM in order to use this new technology, and for desktop machines vendors of PC-compatibles stayed largely with the 16-bit AT bus, ( embraced and renamed as ISA to avoid IBM's " AT " trademark ) and manual configuration, although the VESA Local Bus was briefly popular for Intel ' 486 machines.
VESA and was
An attempt at creating a standard mamed VESA BIOS Extensions ( VBE ) was made, but not all manufacturers used it.
USB signals are not incorporated into the connector, but were earlier incorporated into the VESA Plug and Display connector used by InFocus on their projector systems, and in the Apple Display Connector, which was used by Apple until 2005.
* VESA Feature Connector ( VFC ), obsolete connector that was often present on older videocards, used as an 8-bit video bus to other devices
According to Kendall Bennett, developer of the VBE / AF standard, the VESA Software Standards Committee was closed down due to a lack of interest resulting from charging high prices for specifications.
At the time DisplayPort was announced, VESA was criticized for developing the specification in secret and having a track record of developing unsuccessful digital interface standards, including Plug & Display and Digital Flat Panel.
Although A. b mice and keyboards have been available ( in limited fashion ) for some time, the only serious attempt to use the system was by the VESA group.
DPMS 1. 0 was issued by VESA in 1993, and was based on the United States Environmental Protection Agency's ( EPA ) earlier Energy Star power management specifications.
In the event, the new EISA bus was itself a commercial failure beyond the high end: By the time the cost of implementing EISA was reduced to the extent that it would be implemented in most desktop PCs, the much cheaper VESA Local Bus had removed most of the need for it in desktop PCs ( though it remained common in servers due to for example the possibility of data corruption on hard disk drives attached to VLB controllers ), and Intel's PCI bus was just around the corner.
The closest to an " official " definition was in the VBE extensions defined by the Video Electronics Standards Association ( VESA ), an open consortium set up to promote interoperability and define standards.
Though Super VGA cards appeared in the same year as VGA ( 1987 ), it wasn't until 1989 that a standard for programming Super VGA modes was defined by VESA.
Consisting of two chips, one drawing the graphics known as the P9000 and another handling the output, the VideoPower 5x86, the POWER series was used in a number of 3rd party designs based on the VESA Local Bus standard.
An alternative stand or a wall mount could be used with a VESA mount adapter kit that was sold separately.
VESA and designed
NiTro-VLB was a computer system that used a QED R4600 microprocessor implemented on a VESA Local Bus peripheral card and designed to function when connected to a host computer system using an Intel i486.
VESA and problem
The separate slow DOS chip was a problem for owners who played DOS games because these chips were quite slow and had limited and buggy VESA BIOS Extensions implementations.
VESA and ISA
PCI video cards replaced ISA and VESA cards, until growing bandwidth requirements outgrew the capabilities of PCI ; the preferred interface for video cards became AGP, and then PCI Express.
However most still had either PCI or VLB slots alongside the still-ubiquitous ISA slots, and so-called " VIP " ( VESA / ISA / PCI ) boards with all three slot types were also produced.
The Feature connector was an internal connector found mostly in some older VESA Local Bus, ISA and PCI graphics cards, but also on some early AGP ones.
Their speeds often far exceeded the speed of normal ISA or even early PCI buses, e. g. 40 MByte / s for a standard ISA-based SVGA, up to 150 MByte / s for a PCI or VESA-based one, while the standard 16 bit ISA bus ran at ~ 5. 3 MByte / s and the VESA bus at up to 160 MByte / s bandwidth.
0.294 seconds.