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AST RESEARCH, INC.         TECHNICAL BULLETIN # 0967A              3-27-95

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	 INCOMPATIBLE PCI ADAPTER CARDS AND AST'S PCI BASED COMPUTER SYSTEMS 


PROBLEM

Certain revisions of some PCI (Peripheral Component Interconnect) adapter 
cards do not operate reliably in PCI based computer systems that are 
manufactured by AST.

The PCI card will fail POST intermittently with PCI ERROR:

	83030028 or unreliable transfer of data can occur.

CAUSE

The PCI timing specification is violated.  Specifically, the hold time 
specification is not met.

AST SYSTEMS AFFECTED

All PCI based computer systems.

PCI BOARDS AFFECTED

This problem exists on specific revisions of some PCI adapter boards.  
To date, AST is aware of the following PCI adapter boards being impacted:

	Racal Interlan, PCI T2
	LINQ Systems, LINQnet-PCI Q-1200

This Technical Bulletin can be revised to include other PCI adapter boards, 
if it is determined they exhibit this same symptom.

IDENTIFICATION

The PCI adapter boards that exhibit the symptom contain one of the following 
ASIC chips on the board:

	AM79C970
	AM79C974

The part number for the chip is printed on the top of the ASIC chip.

SOLUTION

This problem has been resolved with an updated ASIC chip.  The updated chips 
contain an "A" at the end of the part number on the ASIC chip.  For example, 
the following ASIC chips do not exhibit the timing problem and are fully 
compatible with all of AST's PCI based computer systems:

	AM79C970A
	AM79C974A

Please contact the manufacturer of the PCI adapter board if an updated adapter 
board is required.