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                           IBM ECA
              Engineering Change Announcement

Parts removed from this machine and returned to IBM must be genuine,
                      unaltered IBM Parts

         IBM World Trade Corporation, CE Department Germany
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 EC NUMBER         :  ECD17925     DATE             : 93-01-28
 MANDATORY         :  N
 AUTOMATIC SHIPMENT:  N            SERVICE CODE     : 33
 PARTS SOURCE      :  FUJI         AVAILABILITY DATE: 92/12
                                                                                
 PURPOSE:                                                                       
 To prevent read error of 320MB HDD SCSI HDD on the PS/55                       
 Model 5571-V1C.                                                                
 This EC improves HDD reliavility against noise of power line.                  
                                                                                

 Type             Machines Affected                             
 Mod.  With       and/or Feature/Device    B/M to be  Serv Syst 
 Stg.  B/M        Description              Installed  Hour Hour 

 Plant  97                                                      

 5571- B/M0005571 AFFECTED S/N             B/M53G7252 00.5 00.5 
   V1C            97G0001  THRU  97G0508                        

                                                                                
 PHYSICAL CHECK:                                                                
 Check a lavel on the 320MB HDD side frame, The following                       
 HDD CARD/FRAME ASM Numbers are affected 320MB HDD.                             
     -----------------------------                                              
     | HDD CARD/FRAME ASM Number |                                              
     |---------------------------|                                              
     |   P/N      |    EC Number |                                              
     |------------|--------------|                                              
     | 93X2484    |    843836    |                                              
     |------------|--------------|                                              
     | 93X0994    |    894702    |                                              
     -----------------------------                                              
                                                                                
 PREREQUISITES: NONE                                                            
                                                                                
 COMPANION: NONE                                                                
                                                                                
 CONCURRENT: NONE                                                               
                                                                                
 DETAIL:                                                                        
 Cut a print pattern of 320MB HDD Control card acoording to                     
 EC installation instruction.                                                   
                                                                                
 NOTES:                                                                         
 This FBM is available for one year.                                            
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