Toshiba 650CT Maintenance Manual page 6

The system board is composed of the following major components:
Intel Pentium processor
The Intel Pentium processor operates at 133 MHz and 2.9/3.3 volts. The math co-
processor and 16 KB cache memory are integrated into Pentium chip.
Level-2 cache memory
Data RAM: 256 KB
- Two 32K x 32-bit pipe-line burst synchronous SRAM chips
- 3.3 volt operation
- Access time 8 ns
Tag RAM: 32 KB (only 8 KB is used)
- One 32K x 8-bit asynchronous SRAM chip
- 3.3 volt operation
- Access time 15 ns
The level-2 cache is a direct map method and a write-through policy.
Standard RAM
16 MB, eight 1Mx16-bit EDO DRAM chips
3.3 volt operation
No parity bit
Access time 60 ns
Data transfer is 64-bit width
BIOS ROM (Flash EEPROM)
256 KB, one 256K x 8-bit chip
- 128 KB are used for the system BIOS
- 64 KB are used for the VGA-BIOS
- 8 KB are used for the plug and play data area
- 8 KB are used for password security
- 16 KB are used for boot strap
- 32 KB are reserved
5 volt operation
Access time 120 ns
Data transfer is 8-bit width
Optional memory
One expansion memory slot is available for 8, 16, 32, and 64 MB memory modules.
8 and 16 MB memory modules consist of 1M x 16-bit chips. 32 and 64 MB memory
modules consist of 4M x 16-bit chips.
EDO DRAM is used
3.3 volt operation
No parity bit
Access time 60 ns
Data transfer is 64-bit width
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650CT