Riser card

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VIA EPIA M860 Mini-ITX mainboard with riser for PCI and PCIe (1 ×)

A card riser is a special expansion card which is used as a kind of "elbow" to the expansion cards, which normally perpendicular to the main board (engl. Mainboard ) are arranged to adjust in their spatial position. Riser cards are often 90-degree "elbows", which mean that the expansion card ( plug-in card ) is no longer arranged vertically, but parallel to the motherboard (but there are also flexible riser cards). The main use is the 19 ″ technology, in which one card in the 1 U housing or three cards in the 2 U housing are installed horizontally in this way.

Up until 2010, two riser cards were used in Apple Mac Pro workstations to connect up to 64 GB of RAM. Since Apple was not yet selling 8GB fully buffered RAM bars at the time, the Mac Pro officially only supported 32 GB.

If the main board itself is designed as a plug-in card, it is plugged onto a backplane .

LPX and NLX were form factors that led bus systems for plug-in cards from the motherboard.

variants

Riser cards are available for PCIe , PCI , AGP , and ISA expansion slots.

A distinction is made between passive and active cards, the latter only existing for PCI or PCIe. The passive versions simply loop through the port (s) using printed conductors, only a few smaller resistors and capacitors are used to ensure a clean signal. Active variants enable several cards to be operated in one slot via a riser card. Here there is a small control electronics on the circuit board, which is responsible for the resource management of the inserted cards. More expensive active riser cards have their own bridge and thus provide a separate bus slot for each card inserted. You can therefore expand the bus of the host system with additional bus systems. Thus it is z. B. possible to expand a PCI slot with an ISA bus using a riser card. Such riser cards can also provide several different bus systems at the same time.

Other riser technologies are Audio Modem Riser (AMR), Communication and Networking Riser (CNR), and Advanced Communications Riser (ACR).

Examples

Web links

Commons : Riser cards  - collection of images, videos and audio files