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Functional Description
2
VP22 Processor
The VP22 motherboard supports a single Intel PGA370 socket Pentium III
or Celeron processor. The Pentium III has a FSB speed of 100/133 MHz
and the Celeron has a FSB speed of 66 MHz. The 815E chipset keeps the
FSB operation at 66/100/133 MHz (auto-selected).
System Memory
The VP22 motherboard supports synchronous DRAM memory and
accepts the standard (unbuffered) SDRAM DIMM memory. SDRAM
speed, type and size is determined by the BIOS reading the DIMM
presence detect bits on the SMBus (System Management Bus). The
SDRAM timing register, which provides the DRAM speed control for the
entire array, must be programmed to use the timings of the slowest
DRAMs installed.
This motherboard supports up to 512MB of SDRAM memory with three
168-pin DIMM sockets. It supports 3.3 V single- or double-sided DIMMs
and the individual SDRAMs on the DIMMs must be (x8) or (x16) parts;
(x4) parts are not supported. The DIMM sockets can be populated in any
order. SDRAM operation at 133MHz and 100MHz is supported.
L2 Cache
The Pentium III has an on-die 256KB L2 Advanced Transfer Cache
(ATC). The on-die cache has a 256-bit data bus from the processor core.
The Celeron has 128KB L2 ATC.
Universal Serial Bus
Three Universal Serial Bus (USB) ports are supported on the VP22
motherboard; two USB ports are located at the rear panel and one 5-pin
header is onboard for internal use. USB allows for the easy addition of
peripherals such as a mouse, keyboard, speakers, etc. Transfer rates up to
12Mb/s are supported. The 12Mb/s high-speed connection requires
shielded cables.