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Cache Memory 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.
 

Jumper Settings (External Cache)

   

Cache Size

J24
   
0K ANY
   
128K 1-2
   
256K 2-3
   
512K 1-2
   

Surface Mount Configurations

       

Cache Chip Type

128K

256K

512K
       
Tag SRAM (U50) One 32Kx8 One 32Kx8 One 32Kx8
       
DB SRAM (U65/66) One 64Kx1 One 64Kx1 One 64Kx1
       
Cache (U60,61,62,63,U46,47,48,49) Four 32Kx8 Eight 128Kx8 Four 128Kx8
       
       

Note
Tag and DB Ram are 15ns. Cache Ram is 20ns.
 

Close-Up Of Cache Sockets

Note
The gap between the U60 and U61 is exaggerated to show that the sockets are separate. There are four banks total but just two are shown here. U15 shows a socket with a chip installed, and U60 shows a socket without a chip installed.
 
EXAMPLE: 128K Cache Memory        ³ EXAMPLE: 512K Cache Memory       ³
          32K Cache Chips         ³          128K Cache Chips        ³

    ΙΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ»ΔΒΔΏ ³ ΙΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ»
    Ίω ω ω ω ω ω ω ω ω ω ω ω ω ωΊO³O³ ³ Ίω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ωΊ
    Ί                           ΗΔΑΔΩ ³ Ί                               Ί
    Ί              U60         (Ί     ³ Ί              U60              Ί
    Ί                           Ί     ³ Ί                              (Ί
    Ίω ω ω ω ω ω ω ω ω ω ω ω ω ωΊ     ³ Ί                               Ί
    ΘΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝΡΝ1/4ΔΒΔΏ ³ Ί                               Ί
    ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³ ³ Ίω ω ω ω ω ω ω ω ω ω ω ω ω ω ω ωΊ
    ΐΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΩ ³ ΘΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝΝ1/4
    ΪΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΏ ³ ΪΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΏ
    ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³ ³ ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³
    ΓΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΕΔΑΔΩ ³ ΓΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΕΔΑΔΩ
    ³              U61          ³     ³ ³              U61          ³
    ΓΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔ΄     ³ ΓΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔΒΔ΄
    ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³     ³ ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³
    ΓΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΒΔΏ ³ ΓΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΕΔΒΔΏ
    ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³ ³ ³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³O³
    ΐΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΩ ³ ΐΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΑΔΩ