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17-13
OVERDRIVE® PROCESSOR SOCKET SPECIFICATION
— Case 3: Alternate voltage source only
If the system is designed with only a programmable voltage source using the VID3-
VID0 pins, then the UP# signal need not be used.
NOTE
The programmable voltage source needs to be able to provide the OverDrive
processor with it’s required power. Refer to Figure 17-9.
17.3.3.
BIOS Considerations
Please refer to the Pentium
®
Pro Processor Developer’s Manual, Volume 2: Programmer’s Ref-
erence Manual (Order Number 242691) for BIOS requirements.
It is the responsibility of the BIOS to detect the type of CPU in the system and program the sup-
port hardware accordingly. In most cases, the BIOS does this by reading the CPU signature,
comparing it to known signatures, and, upon finding a match, executing the corresponding hard-
ware initialization code.
The CPUID instruction is used to determine several processor parameters. Following execution
of the CPUID instruction, bits 12 and 13 of the EAX register can be used to determine if the
processor is an OEM or an OverDrive processor. An OverDrive processor is present if bit 13=0
and bit 12=1.
NOTE
Contact your BIOS vendor to ensure that the OverDrive processor BIOS
requirements have been included.
Figure 17-9. Upgrade Presence Detect Schematic - Case 3
Socket 8
VID3-VID0
On-Board VR
4
Summary of Contents for Pentium Pro Family
Page 17: ...1 Component Introduction ...
Page 26: ...2 Pentium Pro Processor Architecture Overview ...
Page 27: ......
Page 36: ...3 Bus Overview ...
Page 62: ...4 Bus Protocol ...
Page 105: ...5 Bus Transactions and Operations ...
Page 126: ...6 Range Registers ...
Page 131: ...7 Cache Protocol ...
Page 135: ...8 Data Integrity ...
Page 148: ...9 Configuration ...
Page 161: ...10 Pentium Pro Processor Test Access Port TAP ...
Page 172: ...11 Electrical Specifications ...
Page 201: ...12 GTL Interface Specification ...
Page 229: ...13 3 3V Tolerant Signal Quality Specifications ...
Page 233: ...14 Thermal Specifications ...
Page 239: ...15 Mechanical Specifications ...
Page 241: ...15 2 MECHANICAL SPECIFICATIONS s Figure 15 1 Package Dimensions Bottom View ...
Page 252: ...16 Tools ...
Page 260: ...16 8 TOOLS Figure 16 4 Generic MP System Layout for Debug Port Connection ...
Page 264: ...17 OverDrive Processor Socket Specification ...
Page 290: ...A Signals Reference ...
Page 320: ...Index ...
Page 328: ......