American Megatrends Apollo, User Manual

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Chapter 1 Overview 3
System Description,
Continued
Cache Memory The Apollo Pentium PCI motherboard supports 256 KB or 512 KB of L2 secondary cache memory. External
cache memory is Write-through/Write-back. Asynchronous cache memory is supported. 3-2-2-2 and 4-3-3-3
Burst Read/Write is supported with asynchronous secondary cache memory.
The Pentium CPU includes 16 KB of L1 internal cache memory. Internal cache memory is Write-back/Write-
through.
Cache Memory Type Cache Memory Size Maximum System
Memory Cached
L1 Internal 16 KB 128 MB
L2 Secondary 256 KB 64 MB
L2 Secondary 512 KB 128 MB
Cache Access Times The access times for L2 secondary cache memory are:
Host Clock Rate Asynchronous SRAM Access Time
50 MHz 15 ns
60 MHz 15 ns
66.66 MHz 15 ns
CMOS RAM The Apollo Pentium PCI motherboard has 128 bytes of nonvolatile CMOS RAM (NVRAM) to store
system configuration information.
Real Time Clock The Apollo motherboard has a real time clock and CMOS RAM powered by an onboard 3V Lithium battery.
Important
The battery on the motherboard can explode if improperly installed. Handle
the battery according to the battery manufacturer’s instructions. Use only the
recommended type of battery. Discard used batteries according to the battery
manufacturer’s instructions.
Cont’d