Alpha BusAlpha Bus : High-Speed PCI-66 MHz BusGeneral P4's Architecture
- Alpha-Bus is a high-throughput PCI-66 MHz bus that direct attached to North bridge.
- With the Alpha-Bus, Gigabit Ethernet no longer strives for bandwidth against all kind of PCI devices, instead it owns a high-speed data path capable of supporting 1000 Mbps network throughput for itself. This design has sharply streamlined the network bottleneck, and let Gigabit Ethernet operate in full gear.
Gigabit Ethernet on Alpha-Bus:
- The PCI bus of general Pentium 4 is connected to South Bridge with a 33MHz speed and approx. 133MB/s total bandwidth. But the Gigabit Ethernet controller alone has 1000 Mbps (approx. 125MB/s) speed, not even mention that when it operates under duplex mode, at best the speed can be doubled (approx. 250MB/s). Therefore, when Gigabit Ethernet is on PCI-33 bus, whether on-board or add-on card, not only its performance will be greatly limited but the extra data overhead may cause whole system to break down.
- Alpha-Bus is an independent, direct PCI bus links to the North Bridge. This Bus is for Gigabit Ethernet used only. That means, Gigabit Ethernet does not have to share bandwidth with other devices attached to South Bridge, such as hard disk, floppy disk, CD-ROM, USB etc. Alpha-Bus has made AK-SR7 a truly server level mainboard which equips with dual Peer PCI Buses.
- AK-SR7, on the contrary, builds a high speed data path!XPCI-66MHz alpha-Bus capable of supporting high network throughput and dedicated for Gigabit Ethernet only.
General P4's Architecture :
Gigabit Ethernet on Alpha-Bus :
IOMeter Performance Benchmark :