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**What's not included:
All  information included  in  this  file can  be  referenced to  some
document or  picture.  Or at least  should be:-) As a  result of this,
proprietary chip sets, and odd combinations of different chip sets are
not  usually  included.   There  tends  to  be  scant  information  on
proprietary chip sets, i.e.  no  datasheet.  Similarly chip sets built
using some components  from one manufacture and some  from another are
kind of difficult to deal with.

An example  I know of  is a  25 MHz 386  DX motherboard that  uses the
Intel N82230/N82231  (formerly, ZyMOS)  286 chip  set, with  an AUStek
cache Controller.   I know it  existed but there is  no documentation.
So the best I can say you'll have  to take my word that it existed.  I
can't include it because there is no real information there.

Also  not  included  is  anything  that  isn't  a  PC-compatible  chip
set.  I.e.  no Macintosh  info.  Any Information  on PC-incompatibles/
pseudo-compatibles, and  other weirdi-type  stuff I have  a particular
interest in.  See  the section: 'Info needed on'.  Some information on
video  chip  sets  is  included,  occasionally but  the  focus  is  on
motherboard implementation.

**Who made the first chip set?...
**Spelling errors/mistyped words...
**Info needed on:...
**A note on VESA support of 486 chipsets....
**Datasheets:...
*_IBM...
*ACC Micro...
*ALD...
*ALi...
*AMD . . . . . . . [no datasheets, some info]...
*Chips & Technologies...
*Contaq  . . . . . [no datasheets, some info]...
*Efar Microsystems [no datasheets, some info]...
*ETEQ...
*Faraday...
*Forex . . . . . . [List only, no datasheets found]...
*Intel...
**?????  (Profusion)    c:99
Chips:         
Memory Access Controller (MAC)  
Data Interface Buffer (DIB)
CPUs:          8x P-III Xeon Oct
DRAM Types:    SDRAM PC100 2-way Interleave dual channel
Max Mem:       32GB
ECC/Parity:    ECC
AGP speed:     N/A
Bus Speed:     100
PCI Clock/Bus: 1/3 PCI-66/64



**800 series...
*Headland/G2...
**HT44          Secondary Cache                                c:Jun92
***Info:
The  HT44 is  a  look-aside write-through,  80486SX,  486DX or  486DX2
secondary cache  controller. It is  packaged in an  inexpensive 84-pin
plastic-leaded chip carrier (PLCC).

Architecture
With  its look-aside architecture,  the HT44  fits beside  the CPU-to-
Memory bus  and not in  the data path.   Therefore, once the  HT44 has
been designed  into a  486 system, it  can be populated  for secondary
cache systems or left vacant for non-secondary cache systems. The HT44
is direct-mapped to the available address space.

Performance
The  HT44  has a  number  of  performance  enhancing features.   These
include zero-waitstate burst line fills  to the 486 on secondary cache
hits, and simultaneous 486 and secondary cache updates on read misses.

Memory Configurations
The HT44 supports  cache sizes from 32KBytes to  1MB. Both synchronous
and asynchronous  SRAMs are supported.  25ns SRAMs are  sufficient for
zero-wait-state operation at 33MHz.

Chip Set Support
The HT44 can,  be implemented with minimal glue logic  in a 486 system
with the  HTK340 (code  name Shasta) chip  set.  The registers  in the
HTK340  allow  for programming  of  non-cacheable and  write-protected
areas of  memory. The  HTK340 will support  the HT44  with synchronous
SRAMs only.   Future Headland chip sets will  support both synchronous
and asynchronous SRAM designs.

The HT44  can also be used  with some third-party  chip sets, however,
additional glue logic may be required.

***Versions:...
***Features:...
**Other:...
*HMC (Hulon Microelectronics)...
*Logicstar...
*Motorola...
*OPTi...
*PC CHIPS/Amptron/Atrend/ECS/Elpina/etc...
*SIS...
*Symphony...
*TI (Texas Instruments)...
*UMC...
*Unresearched:...
*VIA...
*VLSI...
*Western Digital...
*Winbond...
*ZyMOS...
*General Sources:...