Intel SL3QA - Pentium III 550 MHz Processor Specification page 70

SC242-based platform designs in which VTT leads the processor input voltage may
reduce the occurrence of the erratum by connecting SC242 pin B20 (RESERVED) to
pin B9 (VTT).
PGA370-based platform designs in which VTT leads the processor input voltage can
reduce the occurrence of the erratum by connecting pin G37 (RESERVED) to
motherboard VTT or short the PGA370 socket pin G37 to AH20 or G35 (both VTT).
Status: For the steppings affected see the Summary of Changes at the beginning of this
section.
E62. Floating-Point Exception Condition May be Deferred
Problem: A floating-point instruction that causes a pending floating-point exception (ES=1) is
normally signaled by the processor on the next waiting FP/MMX™ technology
instruction. In the following set of circumstances, the exception may be delayed or
the FSW register may contain a wrong value:
1. The excepting floating-point instruction is followed by an instruction that accesses
memory across a page (4-Kbyte) boundary or its access results in the update of a
page table dirty/access bit.
2. The memory accessing instruction is immediately followed by a waiting floating-
point or MMX technology instruction.
3. The waiting floating-point or MMX technology instruction retires during a one-
cycle window that coincides with a sequence of internal events related to
instruction cache line eviction.
Implication: The floating-point exception will not be signaled until the next waiting floating-
point/MMX technology instruction. Alternatively it may be signaled with the wrong
TOS and condition code values. This erratum has not been observed in any
commercial software applications.
Workaround: None identified
Status: For the stepping affected see the Summary of Changes at the beginning of this
section.
E63. THERMTRIP# May Not be Asserted as Specified
Problem: THERMTRIP# is a signal on the Pentium® III processor that is asserted when the
core reaches a critical temperature during operation as detailed in the processor
specification. The Pentium® III processor may not assert THERMTRIP# until a much
higher temperature than the one specified is reached.
Implication: The THERMTRIP# feature is not functional on the Pentium® III processor. Note that
this erratum can only occur when the processor is running with a TPLATE
temperature over the maximum specification of 75° C
Workaround: Avoid operation of the Pentium III processor outside of the thermal specifications
defined by the processor specifications.
Status: For the steppings affected see the Summary of Changes at the beginning of this
section.
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Errata
Specification Update