Intel D875PBZ - Page 2

..:: Intel Communication Streaming Architecture ::..

One the most unique features dealing with the new i875P chipset has to be Intelís new Communication Streaming Architecture, or CSA. CSA is Intelís solution to reducing the PCI Network bottleneck that has been holding back the high throughput that Gigabit Ethernet can achieve. If you think about all the devices that rely on the PCI bus as their main data thoroughfare, you can easily realize the effect that removing the Gigabit data traffic from it could have. Network traffic, especially at these high data rates, can create a tremendous burden on the PCI bus itself and quite possibly degrade the performance of the entire system by clogging up the precious PCI bandwidth that is needed for transferal of data for other devices. Whatís worse is, any Gigabit Controllers based off of a PCI connection are already limited in the amount of bandwidth that they can deal with. The theoretical maximum throughput of the PCI bus lies at 1.06 GB/s while the networking interface has a maximum throughput of roughly 2.2 GB/s. Another problem that lies within the PCI bus is that the data must complete operations serially which only adds to the problem of the PCI bus by inducing added latency. With the limited bandwidth of the PCI bus, it makes bi-directional Gigabit data transfers impossible, and limits unidirectional transfers to a mere 1 GB/s, less than half what it is capable of.

Motherboards that feature this new Communications Streaming Architecture can avoid this troublesome issue though its 266 MB/s direct connection to the Memory Controller Hub. This connection allows for higher data transfer rates and lower memory read and write operation latencies. This is due to the direct connection between the network interface and the system RAM. Another bonus of CSA is that it reduces the number of traverses across the interface to the ICH by half, which further aids in the reduction of latencies. The data flows in a very organized manner from the MCH via the CSA, to the RAM, and then to the ICH via the hublink interface.

Well, what does this all mean? This means that users are now fully capable of experiencing a true Gigabit experience with Gigabit transfer rates in both directions. No longer does the controller have to rely on the PCI bus, thereby having to deal with traffic from other devices that utilize the bus. A direct connection between the controller and the MCH allows for lowered latency times, reduced CPU utilization, and more concise and directed data transfers through the various data buses within the system. With the controller removed from the PCI bus, there is now more room for data from other devices such as IEEE1394, scanners, and digital cameras. Other devices such as Serial ATA drives, AC 97í audio, USB 2.0, and optical drives can also now have access to larger amounts of bandwidth furthering their speed and furthering the overall system performance. The Intel 82547EI Gigabit Controller and the i875P chipsets are the bases for the foundation of the CSA-based designs for future motherboards.

..:: Intel 82547EI Gigabit Ethernet Controller ::..

The main phrase used by Intel in describing the 82547EI Gigabit Ethernet Controller is ď2X Gigabit Network Performance for Desktops and Workstations.Ē As we have just seen, the CSA architecture by Intel allows for full duplex Gigabit throughput and higher performance. According to Intelís testing, the connection can achieve somewhere in the area of 1.6 GB/s full duplex compared to a PCI based solutions throughput of around 900 MB/s. Due to the fact that the CSA architecture is invisible to both system software and operating systems alike, the 82547EI Gigabit Ethernet Controller can be configured much like any other PCI type configuration. The 82547EI Gigabit Ethernet Controller allows for true Gigabit transfer rates for LOM (LAN on Motherboard) applications through the use of its CSA bus.

The 82547EI Gigabit Ethernet Controller enhances overall secure management and system health monitoring over the LAN with support of features such as IPMI 1.5, ASF 2.0, and Advanced Pass Through. The onboard SMBus is capable of transferring management traffic through the controller to a management device responsible for its given functions. This applies to the IPMI 1.5 designs. The ASF 2.0 designs provide manageability without the added costs of other hardware that might be needed for external connection via the additional standard interfaces. ASF 2.0 provides advanced health and security alerts along with options such as remote power controlling capabilities.

To quote Intel about their 82547EI Gigabit Ethernet Controller, ďThe 82547EI combines Intelís fifth-generation Gigabit MAC design with fully integrated physical layer circuitry to provide a standard IEEE 802.3 Ethernet interface for 1000BASE-T, 100BASE-TX and 10-BASET applications.Ē The 82547EI Gigabit Ethernet Controller comes in a small 15mm x 15mm PBGA package allowing for a small footprint which is also compatible with other Intel controllers such as the 82562EX and 82562EZ. This allows for quicker implementation from mainboard manufacturers wishing to switch to a Gigabit Ethernet implementation on current motherboard designs without facing the hassles of having to deal with layout re-design.

Now that we've had a chance to cover some of the new features of the i875P chipset, let's take a look at the D875PBZ "Bonanza" motherboard from Intel which is, of course, based off of the i875P chipset to see just how well this board performs, along with the feature set and other items that we are accustomed to taking a look at.