Reply 55 Turboboard

Also called Model 55 486SLC2 System Board Upgrade

193-313 IBM Planar Upgrades For PS/2 Models 50, 50Z, 55 SX And LS
rf5055pu.exe  PS/2 8550/50Z/55 planar upgrade refdisk v1.01

Please tell me of repressed memories about this planar!

"CD-ROM connector" is errata, that is the normal 55 bus riser.

Reply 55 Turboboard Image (thanks to nyce-distribution)

I need to review the image and pull out chip IDs.

F1 Fuse
J1 Mouse
J2 Keyboard
J3 Parallel
J4 Serial
J5 Video
J7 Solder pads
J9 Solder pads
J8 12 pin header
J10 Solder pads
J11 Password Override
J12 4 pin power
J15 floppy
J17 solder pads
M1,2,3 SIMM sockets
U3 22.1184 MHz osc
U7 LT1141CS
U9 14.3181 MHz osc
U11 CL-GD5426-80QC
U12 10G4672
U18 Dallas DS1387
U19, 20 KM416C256AJ-7
U21, 22 solder pads
U29 N82077SL
U47 PLCC 02N3251 G1.04
U48 96F7690
U49 50G6950 IBM 486SLC2
U61 50.0000MHz osc
U63 PLCC socket upgrade cpu?
Y1 ? xtal

CPU- 486SLC2 25/50 Copro 387SX 
Max Memory on board 16MB  2, 4, or 8MB, 70nS parity 
Three SIMM Sockets, 70ns, 80ns and 85ns memory SIMMs

Three 16-bit MCA slots (includes one AVE) 

Video Controller CL-GD5426-80QC
Video Memory- 1MB DRAM (2 SOJ) 
640x480, 16M: 24 bits/pixel 
800x600, 64K: 16 bits/pixel 
1,024x768, 256: 8 bits/pixel 
Parallel: One enhanced, bi-di with DMA support/
Serial - one enhanced with DMA support 
HD Support AT/IDE and existing drive 
Floppy controller supports 1.44 and 2.88MB floppies 
Clock/calendar integrated CMOS battery 

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