X6800 Datasheet, PDF (31/122 Pages) Intel Corporation – Core2 Extreme Processor

Electrical Specifications
2.7.4 Clock Specifications
2.7.5
Table 16.
2.7.6
Front Side Bus Clock (BCLK[1:0]) and Processor Clocking
BCLK[1:0] directly controls the FSB interface speed as well as the core frequency of the
processor. As in previous generation processors, the processor’s core frequency is a
multiple of the BCLK[1:0] frequency. The processor bus ratio multiplier will be set at its
default ratio during manufacturing. Refer to Table 16 for the processor supported
ratios.
The processor uses a differential clocking implementation. For more information on the
processor clocking, contact your Intel Field representative. Platforms using a CK505
Clock Synthesizer/Driver should comply with the specifications in Section 2.7.8.
Platforms using a CK410 Clock Synthesizer/Driver should comply with the specifications
in Section 2.7.9.
Core Frequency to FSB Multiplier Configuration
Multiplication of
System Core
Frequency to FSB
Frequency
Core Frequency
(200 MHz BCLK/
800 MHz FSB)
Core Frequency
(266 MHz BCLK/
1066 MHz FSB)
Core Frequency
(333 MHz BCLK/ Notes^{1, 2}
1333 MHz FSB)
1/6
1.20 GHz
1.60 GHz
2.00 GHz
-
1/7
1.40 GHz
1.87 GHz
2.33 GHz
-
1/8
1.60 GHz
2.13 GHz
2.66 GHz
-
1/9
1.80 GHz
2.40 GHz
3.00 GHz
-
1/10
2 GHz
2.66 GHz
3.33 GHz
-
1/11
2.2 GHz
2.93 GHz
3.66 GHz
-
1/12
2.4 GHz
3.20 GHz
4.00 GHz
NOTES:
1. Individual processors operate only at or below the rated frequency.
2. Listed frequencies are not necessarily committed production frequencies.
FSB Frequency Select Signals (BSEL[2:0])
The BSEL[2:0] signals are used to select the frequency of the processor input clock
(BCLK[1:0]). Table 17 defines the possible combinations of the signals and the
frequency associated with each combination. The required frequency is determined by
the processor, chipset, and clock synthesizer. All agents must operate at the same
frequency.
The Intel Core2 Duo desktop processors E6850, E6750, E6550, and E6540 operate at
1333 MHz (selected by the 333 MHz BCLK[2:0] frequency). The Intel Core2 Duo
desktop processors E6700, E6600, E6420, E6400, E6320, and E6300 operate at
1066 MHz (selected by the 266 MHz BCLK[2:0] frequency). The Intel Core2 Extreme
processor X6800 operates at a 1066 MHz FSB frequency (selected by a 266 MHz
BCLK[1:0] frequency). The Intel Core2 Duo desktop processors E4600, E4500, E4400
and E4300 operate at a 800 MHz FSB frequency (selected by a 200 MHz BCLK[1:0]
frequency).
Datasheet
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