Intel Xeon Instruction Manual

Intel®Xeon™ Processor with 512 KB
L2 Cache System Compatibility
Guidelines
Order Number: 298645-001
January 2002

Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
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mation. Revised information will be published when the product is available. Verify with your local sales office that you have
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Copyright © Intel Corporation 2002.

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Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
Table of Contents
1.0 Revision History.................................................................................. 4
2.0 Introduction......................................................................................... 5
1.1 Audience.......................................................................................... 5
1.2 References ...................................................................................... 5
3.0 Compatibility ....................................................................................... 6
4.0 SM_VCC............................................................................................. 6
5.0 603-Pin Socket Pin Definition Changes.............................................. 6
6.0 VCC Power Sequencing...................................................................... 7
7.0 Power and Signal Levels .................................................................. 10
8.0 VRM 9.0 and VRM 9.1...................................................................... 10
9.0 Core Frequency to System Bus Ratio Determination....................... 10

Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
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1.0 Revision History
Revision Date Changes
-001 January 2002 Initial Release

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Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
2.0 Introduction
This document describes the required changes to Intel® Xeon™ processor-based
platforms in order to provide Intel® Xeon™ processor with 512 KB L2 cache compatibility.
The information in this document should be used in conjunction with specifications
presented in the latest version of the Intel® Xeon™ Processor with 512 KB L2 Cache at
1.80 GHz, 2 GHz, and 2.20 GHz Datasheet and Intel® Xeon™ Processor at 1.40 GHz,
1.50 GHz, 1.70 GHz and 2 GHz Datasheet,as well as information provided in other
processor related design guides listed in the References section below. Design decisions
should always be based on information contained in the latest applicable processor
datasheet. For proper and reliable processor operation, the designer must ensure that the
requirements in this guideline are fully satisfied.
2.1 Audience
This document is targeted at the following audience:
•Intel Xeon processor-based system developers who want to ensure system
compatibility with the Intel Xeon processor with 512 KB L2 cache.
2.2 References
Material and concepts available in the following documents may be beneficial when
reading this document:
•Intel® Xeon™ Processor with 512 KB L2 Cache at 1.80 GHz, 2 GHz, and 2.20 GHz
Datasheet
•Intel® Xeon™ Processor at 1.40 GHz, 1.50 GHz, 1.70 GHz and 2 GHz Datasheet
•Intel® Xeon™ Processor and Intel® 860 Chipset Platform Design Guidelines
•VRM 9.0 DC-DC Converter Design Guidelines
•VRM 9.1 DC-DC Converter Design Guidelines
•Dual Intel® Xeon™ Processor Voltage Regulator Down (VRD) Design Guidelines
•Intel® Xeon™ Processor Thermal Design Guidelines
•ATX/ATX12V Power Supply Design Guide (available at http://www.formfactors.org)
•MPS Power Supply: A Server System Infrastructure (SSI) Specification For Midrange
Chassis Power Supplies (available at http://www.ssiforum.org)

Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
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3.0 Compatibility
Implementing the changes outlined in this document will help assure that an Intel®
Xeon™ processor-based system design will be compatible with the Intel Xeon processor
with 512 KB L2 cache. Compatibility is likely to be ultimately limited by the ability of the
system to supply the required current and to adequately cool the processor.
4.0 SM_VCC
SM_VCC must be connected to the system 3.3 volt power supply since the Intel® Xeon™
processor with 512 KB L2 cache drives the voltage identification (VID) outputs using core
circuitry powered by the SM_VCC supply.
Refer to Section 6.0 for further considerations involving the power sequencing
requirements of SM_VCC
5.0 603-Pin Socket Pin Definition Changes
The Intel® Xeon™ processor with 512 KB L2 cache is mechanically and electrically
compatible with the same 603-pin socket used for the Intel Xeon processor. However, in
order to support the increased frequencies offered by the Intel Xeon processor with 512
KB L2 cache, "Reserved" and "N.C." pins from the original Intel Xeon processor pin
definition have been designated as either VCC or VSS. Intel Xeon processor-based
platforms need to redefine the 603-pin socket pin map as listed in the “New Name”
column of Table 1 to allow compatibility with the Intel Xeon processor with 512 KB L2
cache.
Table 1. 603-Pin Socket Pin-Map Change
Pin Old Name New Name Comment
A30 RSVD VCC Processor Power
A31 RSVD VSS Processor Ground
B4 RSVD VCC Processor Power
B30 RSVD VSS Processor Ground
B31 RSVD VCC Processor Power
C1 RSVD VSS Processor Ground
C30 RSVD VCC Processor Power
C31 RSVD VSS Processor Ground
D1 RSVD VCC Processor Power
D30 RSVD VSS Processor Ground

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Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
D31 RSVD VCC Processor Power
E1 RSVD VSS Processor Ground
E30 RSVD VCC Processor Power
E31 RSVD VSS Processor Ground
F1 RSVD VCC Processor Power
F30 RSVD VSS Processor Ground
F31 RSVD VCC Processor Power
G1 RSVD VSS Processor Ground
G30 RSVD VCC Processor Power
G31 RSVD VSS Processor Ground
H1 RSVD VCC Processor Power
H30 RSVD VSS Processor Ground
H31 RSVD VCC Processor Power
J1 RSVD VSS Processor Ground
J30 RSVD VCC Processor Power
J31 RSVD VSS Processor Ground
K1 RSVD VCC Processor Power
K30 RSVD VSS Processor Ground
K31 RSVD VCC Processor Power
L1 RSVD VSS Processor Ground
L30 RSVD VCC Processor Power
L31 RSVD VSS Processor Ground
M1 RSVD VCC Processor Power
M30 RSVD VSS Processor Ground
M31 RSVD VCC Processor Power
N1 RSVD VCC Processor Power
N30 RSVD VSS Processor Ground
N31 RSVD VCC Processor Power
P1 RSVD VSS Processor Ground
P30 RSVD VCC Processor Power
P31 RSVD VSS Processor Ground
R1 RSVD VCC Processor Power
R30 RSVD VSS Processor Ground
R31 RSVD VCC Processor Power
T1 RSVD VSS Processor Ground
T30 RSVD VCC Processor Power
T31 RSVD VSS Processor Ground
U1 RSVD VCC Processor Power
Table 1. 603-Pin Socket Pin-Map Change
Pin Old Name New Name Comment

Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
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6.0 VCC Power Sequencing
As outlined in Section 4.0, a 3.3 volt power supply must be connected to the Intel®
Xeon™ processor with 512 KB L2 cache SM_VCC pins (AE28 & AE29). SM_VCC is the
supply voltage used for the SMBus functions and for the VID output signal circuits. The
VID signals are programmed by Intel during the manufacturing process so that the VRM
output voltage will be set correctly. As indicated in Figure 1, the VID outputs will be valid
within 10 milliseconds after the time at which the 3.3 volt supply reaches 95% of its
nominal value. For a power supply that adheres to the ATX12V power supply design
guidelines, PWR_OK will be generated no less than 100 milliseconds after all of its
outputs reach their respective 95% values (please refer to the document ATX/ATX12V
Power Supply Design Guide). Similarly, for a power supply that adheres to the Server
System Infrastructure (SSI) power supply specification, PWR_OK will be generated no
less than 100 milliseconds after all of its outputs are within their respective regulation
limits (please refer to the document MPS Power Supply: A Server System Infrastructure
(SSI) Specification For Midrange Chassis Power Supplies).PWR_OKmaybeusedto
enable the output of the VRM (VCC) using the OUTEN signal. The VRM PWRGD output,
in conjunction with the rest of the system’s powergood logic, may be used to generate the
U30 RSVD VSS Processor Ground
U31 RSVD VCC Processor Power
V1 RSVD VSS Processor Ground
V30 RSVD VCC Processor Power
V31 RSVD VSS Processor Ground
W1 RSVD VCC Processor Power
W30 RSVD VSS Processor Ground
W31 RSVD VCC Processor Power
Y1 RSVD VSS Processor Ground
Y30 RSVD VCC Processor Power
Y31 RSVD VSS Processor Ground
AA1 RSVD VCC Processor Power
AA30 RSVD VSS Processor Ground
AA31 RSVD VCC Processor Power
AB1 RSVD VSS Processor Ground
AB30 RSVD VCC Processor Power
AB31 RSVD VSS Processor Ground
AC30 RSVD VSS Processor Ground
AC31 RSVD VCC Processor Power
AD30 RSVD VCC Processor Power
AD31 RSVD VSS Processor Ground
Table 1. 603-Pin Socket Pin-Map Change
Pin Old Name New Name Comment

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Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
PWRGOOD input to the processor. PWR_OK will be deasserted when any output of an
ATX12V-compliant or SSI-compliant power supply falls below regulation limits. It is
important to maintain SM_VCC at any time the output of the VRM is enabled. Driving the
VRM’s OUTEN with the PWR_OK signal will ensure correct sequencing at both power up
and power down.
Figure 1. Voltage Sequence Timing Requirements
VRM
Power
Supply
Processor
VID[4:0]
3.3 VDC
PWR_OK
OUTEN
PWRGD
PWRGOOD
SM_VCC
3.3 VDC/SM_VCC
PWROK
OUTEN
Power Down
3.3 VDC/SM_VCC
PWR_OK /
VID_OUT
OUTEN
VRM
PWRGD
Processor
PWRGOOD
Processor
RESET
T0= 95% 3.3 volt level Power Up
SM_VCC out of
regulation
T0+10mS
> valid p/s voltages + 100 ms
Power Down Warning > 1ms
1ms < T
36 <10ms
System
PWRGD
Logic
...
... VID
VID

Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
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7.0 Power and Signal Levels
The VID for the Intel® Xeon™ processor with 512 KB L2 cache is 1.500 volts compared to
a VID level of 1.700 volts for the Intel Xeon processor. The Intel Xeon processor with 512
KB L2 cache still uses a single core voltage supply (VCC) to supply the termination voltage
(VTT). Table 2 outlines changes to the way AGTL+ signal level specifications are defined
for the Intel Xeon processor with 512 KB L2 cache. The Intel Xeon processor with 512 KB
L2 cache defines the VIH and VIL specifications based on a percentage of the GTLREF
level instead of a fixed voltage offset level. In Table 2, use a value of GTLREF = 2/3*VCC
for both processors. It is important to simulate the system bus to ensure that these levels
are met. Other bus electrical characteristics are expected to be compatible with the Intel®
Xeon™ processor specifications. Refer to the processor datasheets given in Section 2.2
for complete details regarding all processor specifications referenced in this section.
NOTE: These values are for reference only. The latest processor datasheet contains the actual specifications
for the processor. If the specifications in this table conflict with the specifications found in the datasheet,
the datasheet supersedes.
8.0 VRM 9.0 and VRM 9.1
Voltage regulator designs for Intel® Xeon™ processor-based platforms were initially
basedonIntel’sVRM 9.0 DC-DC Converter Design Guidelines. However, to provide
additional VRM high current capability for new platforms, Intel created an updated voltage
regulator design guide entitled VRM 9.1 DC-DC Converter Design Guidelines. Intel Xeon
processor platforms intending to support the Intel Xeon processor with 512 KB L2 cache
are not required to upgrade to VRM 9.1 and may continue to use VRM 9.0 voltage
regulator solutions. However, new platforms should consider implementing VRM 9.1 since
it provides the most recent voltage regulator design guidelines for the Intel Xeon
processor with 512 KB L2 cache.
9.0 Core Frequency to System Bus Ratio Determination
The core frequency to system bus ratio for the Intel® Xeon™ processor is configured by
driving the ratio select signals (LINT[1]/NMI, A20M#, IGNNE#, and LINT[0]/INTR) with
appropriate ratio encoding values during processor power-on reset. The Intel Xeon
processor with 512 KB L2 cache implements a new method for setting the core frequency
to system bus ratio and will ignore the ratio select signals at power-on reset. The Intel
Table 2. AGTL+ Signal Changes
Symbol Intel® Xeon™ Processor Intel® Xeon™ Processor
with 512 KB L2 Cache
VIL Max GTLREF - 0.100 0.90*GTLREF
VIH Min GTLREF + 0.100 1.10*GTLREF

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Intel® Xeon™ Processor with 512 KB L2 Cache System Compatibility Guidelines
Xeon processor with 512 KB L2 cache operates at its tested frequency at initial power-on.
If the processor needs to run at a lower core frequency, as must be done when a higher
speed processor is added to a system that contains a lower frequency processor, the
system BIOS is able to effect the change in the core to system bus ratio.