PB400/PB401T CPU Upgrade Information
| Warning |
Only authorized service personnel should upgrade the system.
Anyone who wants to upgrade the system herself/himself should know about the dangers of ESD (Electro-Static Discharge) and the necessary precautions. Unknowingly zapping the components of the computer will void the warranty. |
Math Co-Processor
This system will support a variety of processors. They can be located in U73 and/or U74.
The PB400 uses 238 pin type 2 socket. It DOES NOT support P24T over drive processor.
Note |
| This upgrade must be done by an authorized service center technician for systems still under warranty. The Overdrive processor must be removed prior to any onsite service, in the event that the motherboard is being swapped with a new one.
|
Intel has changed the designations of the 80486 OverDrive processors. In the table below, the original designations are in parenthesis.
The following jumpers are used
|
J30 (Jcpus) |
Indicates the processor in use. This jumper has 10 pins. |
J31 (Jcpup) |
Indicates if the processor is located in the CPU socket or the Upgrade Processor socket. |
J34 (Jfcpu) |
Indicates if the processor in use is a fast CPU (DX2 or Overdrive Processor). |
J35 (Jfreq) |
Indicates the speed of the CPU. This jumper has 4 pins. |
╔═══════════╤════════════╦════╤════╤════╤════╤════╦════╦════╦════╤════╗
║CPU (U73)│UPGRADE ║J30 │J30 │J30 │J30 │J30 ║J31 ║J34 ║J35 │J35 ║
║SOCKET │SOCKET (U74)║1-2 │3-4 │5-6 │7-8 │9-10║1-2 ║1-2 ║1-2 │3-4 ║
╠═══════════╪════════════╬════╪════╪════╪════╪════╬════╬════╬════╪════╣
║486SX-20 │None ║Out │In │Out │Out │Out ║Out ║Out ║Out │In ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486SX-20 * │None ║In │In │Out │Out │Out ║Out ║Out ║Out │In ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486SX-20 │487SX-20 ║In │Out │In │Out │In ║In ║Out ║Out │In ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486SX-20 │DX2ODP50 ║In │Out │In │In │Out ║In ║In ║Out │In ║
║ │(ODP486SX20)║ │ │ │ │ ║ ║ ║ │ ║
╠═══════════╪════════════╬════╪════╪════╪════╪════╬════╬════╬════╪════╣
║486SX-25 │None ║Out │In │Out │Out │Out ║Out ║Out ║In │Out ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486SX-25 * │None ║In │In │Out │Out │Out ║Out ║Out ║In │Out ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486SX25 │487SX-25 ║In │Out │In │Out │In ║In ║Out ║In │Out ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486SX25 │DX2ODP50 ║In │Out │In │In │Out ║In ║In ║In │Out ║
║ │(ODP486SX25)║ │ │ │ │ ║ ║ ║ │ ║
║ │or ║ │ │ │ │ ║ ║ ║ │ ║
║ │DX4-75 5V ║ │ │ │ │ ║ ║ ║ │ ║
╠═══════════╪════════════╬════╪════╪════╪════╪════╬════╬════╬════╪════╣
║486DX33 │None ║In │Out │In │In │Out ║Out ║Out ║Out │Out ║
╟───────────┼────────────╫────┼────┼────┼────┼────╫────╫────╫────┼────╢
║486DX33 │DX2ODP66 ║In │Out │In │In │Out ║In ║In ║Out │Out ║
║ │(ODP486SX33)║ │ │ │ │ ║ ║ ║ │ ║
║ │or ║ │ │ │ │ ║ ║ ║ │ ║
║ │DX4-100 5V ║ │ │ │ │ ║ ║ ║ │ ║
╠═══════════╪════════════╬════╪════╪════╪════╪════╬════╬════╬════╪════╣
║486DX2-50 │None ║In │Out │In │In │Out ║Out ║In ║In │Out ║
╠═══════════╪════════════╬════╪════╪════╪════╪════╬════╬════╬════╪════╣
║486DX2-66 │None ║In │Out │In │In │Out ║Out ║In ║Out │Out ║
╚═══════════╧════════════╩════╧════╧════╧════╧════╩════╩════╩════╧════╝
* for surface mount type CPU (PQFP)