Soyo SY-P4ISR (845 SDRAM) Mainboard
The Pentium 4 was introduced
along with Intel's 850 chipset, not long ago it was the only solution available
for the Pentium 4; obligating people to use it without giving them choice
to go with an alternative solution. The 850 is Intel's high end solution for
the Pentium 4, mainboards based on the 850 cost more and use the more expensive
RDRAM memory. In order to spread the Pentium 4 more into the mainstream market,
an alternate chipset had to be introduced.
The 845 chipset is Intel's solution to get the Pentium 4 into the mainstream
market; the chip costs lower to produce, the new core logic allows mainboard
makers to get back to the lower cost four-layer PCB's and at the same time
takes use of the less expensive SDRAM or DDR SDRAM memory. We are looking
at the DFI NB72-SR; an 845 SDRAM based Pentium 4 mainboard.
- Intel 845 Chipset
- 6 PCI slots
- 1 CNR
- Onboard Audio
- Supports PC133
- AC`97 Audio codec
- RAID 0 or 1
- Socket 478
Intel introduced their
845 chipset earlier this year in order to accommodate their Pentium 4 with
a value segment chip which costs less to produce and eliminating the need
of using the expensive RDRAM memory. The South Bridge of the 845, ICH2, is
the same as in the high end 850 chip which supports 4 USB 1.1 ports, ATA/100
support, CNR/AMR slots and a 6 channel AC"97 audio along with a LAN interface.
The North Bridge features
support for the Pentium 4 processor running at 400MHz Quad Pumped Bus, supports
3GB of memory for PC133 SDRAM or 2GB of PC1600/PC2100 DDR SDRAM along with
AGP4X. Note that as Intel positioned the 845 as a value segment, ECC support
is not available on the memory controller.
The 845D (DDR) and 845
(PC133) versions offer the same features; both share the same ICH2 hub. The
only difference between the 845D (DDR) and the 845 (SDRAM) is the memory controller
which features support for DDR SDRAM.
Intel 845 Schematic