14 DAY TRIAL // Microprocessor giant Intel is considering having a new PCI Express interface introduced in the PCIe standard which should provide two such lanes to the peripheral devices and chips that are usually installed on motherboards.
The Santa Clara-based company hopes that by going this route it will be able to remove the bottlenecks faced by bandwidth hungry devices that are forced to use PCI Express x1 links, without having to allocate a full four lanes to such peripherals.
Outside of the fact that a PCI Express x4 link is too wide for many of the motherboard chips that require PCIe connectivity, Intel also has only a limited number of such lanes available in its PCH controllers.
For example, the Cougar Point chipsets, used in all the LGA 1155 motherboards currently on the market, support a maximum of eight PCI Express lanes, which could mean that only two peripherals could be enabled at the same time.
Going for a PCI Express x2 interface would increase this number to four, or it could allow for installing a PCIe x4 motherboard slot as well as two PCIe x2 peripheral chips.
Right now motherboard makers use the PCI Express lanes available in the Cougar Point chipsets to install USB 3.0 controllers, SATA 6Gbps controllers and/or high-quality audio chipsets.
Since a single SATA 6Gbps port has a peak throughput of about 600MB/s it quickly becomes apparent how a single PCI Express 2.0 lane (which has a theoretical maximum transfer speed of 500MB/s) can't provide enough bandwidth for such a controller.
The arrival of the Panther Point chipsets could alleviate some of these problems as additional PCI Express lanes will be freed thanks to the native USB 3.0 support, but Intel's upcoming PCH is still limited at supporting two 6Gbps SATA ports, so motherboard makers will have to resort to third-party controllers in their flagship products.
Before bringing such an interface to its products, Intel will have to gain the support of PCI-SIG organization, which controls the PCI Express standard and its specifications. (via VR-Zone)
