Intel® Xeon® Processor E5-1600/E5-2600/E5-4600 Product Families 165
Datasheet Volume One
Electrical Specifications
7.4 Fault Resilient Booting (FRB)
The processor supports both socket and core level Fault Resilient Booting (FRB), which
provides the ability to boot the system as long as there is one processor functional in
the system. One limitation to socket level FRB is that the system cannot boot if the
legacy socket that connects to an active PCH becomes unavailable since this is the path
to the system BIOS. See Tabl e 7-8 for a list of output tri-state FRB signals.
Socket level FRB will tri-state processor outputs via the PROCHOT_N signal. Assertion
of the PROCHOT_N signal through RESET_N de-assertion will tri-state processor
outputs. Note, that individual core disabling is also supported for those cases where
disabling the entire package is not desired.
The processor extends the FRB capability to the core granularity by maintaining a
register in the uncore so that BIOS or another entity can disable one or more specific
processor cores.
7.5 Mixing Processors
Intel supports and validates and four two processor configurations only in which all
processors operate with the same Intel QuickPath Interconnect frequency, core
frequency, power segment, and have the same internal cache sizes. Mixing
components operating at different internal clock frequencies is not supported and will
not be validated by Intel. Combining processors from different power segments is also
not supported.
Note: Processors within a system must operate at the same frequency per bits [15:8] of the
FLEX_RATIO MSR (Address: 194h); however this does not apply to frequency
transitions initiated due to thermal events, Extended HALT, Enhanced Intel SpeedStep
Table 7-8. Fault Resilient Booting (Output Tri-State) Signals
Output Tri-State Signal Groups Signals
Intel QPI
QPI0_CLKTX_DN[1:0]
QPI0_CLKTX_DP[1:0]
QPI0_DTX_DN[19:00]
QPI0_DTX_DP[19:00]
QPI1_CLKTX_DN[1:0]
QPI1_CLKTX_DP[1:0]
QPI1_DTX_DN[19:00]
QPI1_DTX_DP[19:00]
SMBus
DDR_SCL_C01
DDR_SDA_C01
DDR_SCL_C23
DDR_SDA_C23
PEHPSCL
PEHPSDA
JTAG & TAP TDO
Processor Sideband
CAT_ERR_N
ERROR_N[2:0]
BPM_N[7:0]
PRDY_N
THERMTRIP_N
PROCHOT_N
PECI
SVID SVIDCLK