109
A
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p
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n
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8
8
6
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5
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F
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a
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m
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M
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M
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a
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C
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N
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R
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C
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The CNR specification provides the PC industry the opportunity to deliver a flexible and cost reduced method of implementing LAN,
home networking, DSL, USB, wireless, audio and modem subsystems widely used in today's "connected PCs". The CNR specification is
an open industry specification and is supported by OEMs, IHV card manufacturers, silicon supplier and Microsoft.
D
D
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S
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D
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DDR SDRAM utilizes the existing
SDRAM
(For ex, PC-100, PC-133) infrastructure and technology while doubling the nominal
bandwidth available to systems in an easy to design and simple to adopt way. Based on FSB frequency, DDR SDRAM on the market
are DDR200, DDR266 and DDR333 with more coming around soon.
DDR200
, transfer bandwidth up to 200x64/8=1600MB/s (PC1600)
DDR266
, transfer bandwidth up to 266x64/8=2100MB/s (PC2100)
DDR333
, transfer bandwidth up to 333x64/8=2700MB/s (PC2700)
DDR400
, transfer bandwidth up to 400x64/8=3200MB/s (PC3200)
E
E
C
C
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The ECC mode needs 8 ECC bits for 64-bit data. Each time memory is accessed; ECC bits are updated and checked by a special
algorithm. The ECC algorithm has the ability to detect double-bit error and automatically correct single-bit error while parity mode can
only detect single-bit error.
E
E
E
E
P
P
R
R
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M
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(
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E
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Also be known as E
2
PROM. Both EEPROM and
Flash ROM
can be re-programmed by electronic signals, but the interface technology is
different. Size of EEPROM is much smaller than flash ROM.
