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Two Xeon CPUs Are Better Than One Intel P4 Extreme Platform

Data Transfer Rates Depending On PCI Standard

StandardBitClockTransfer rates(bi-directional)
PCI 2.332 Bit33 MHz133 MB/sec
PCI 2.332 Bit66 MHz266 MB/sec
PCI 6464 Bit33 MHz266 MB/sec
PCI 6464 Bit66 MHz533 MB/sec
PCI-X 1.064 Bit66 MHz533 MB/sec
PCI-X 1.064 Bit100 MHz800 MB/sec
PCI-X 1.064 Bit133 MHz1066 MB/sec
PCI-X 2.0 (DDR)64 Bit133 MHz2132 MB/sec
PCI-X 2.0 (QDR)64 Bit133 MHz4264 MB/sec
PCI-Express1 Lines 8 Bit2.5 GHz512 MB/sec
PCI-Express2 Lines 8 Bit2.5 GHz1 GB/sec
PCI-Express4 Lines 8 Bit2.5 GHz2 GB/sec
PCI-Express8 Lines 8 Bit2.5 GHz4 GB/sec
PCI-Express16 Lines 8 Bit2.5 GHz8 GB/sec

The HUB 2 connection offers a maximum data transfer rate of 1 GB per second between Southbridge and Northbridge, the following combination possibilities resulting for a maximum interface load for a P64H2 chip:

  1. 1x PCI-X 133 MHz = 1066 MB/sec
  2. 1x PCI-X 100 MHz = 800 MB/sec
  3. 2x PCI-X 66 MHz = 1066 MB/sec
  4. 2x PCI 64 66 MHz = 1066 MB/sec
  5. 3x PCI 64 33 MHz = 798 MB/sec

Standard cards do not exhaust data transfer rates of 1,066 MB per second. Only high-performance products, such as SCSI320 cards (320 MB/s) or 10 GB LAN chips (max. 1250 MB per second), would be sensible candidates.

Many PCI cards are capable of performing their services not only with conventional PCI 2.3 slots, but also with a PCI 64 slot. Examples of these are network cards, RAID controllers and even 56K modems. In order to avoid incorrect configurations, they have an additional notch on the connection contacts.

A 56K modem for a 64 bit slot

The 56K modem operates here with conventional 33 MHz in 32 bit mode.

A Promise SATA controller for a 64 bit slot

This Raid controller can handle even 66 MHz in 32 bit mode.