Chingshun J Cheng

51558440, Oct 13, 1992

Feb 14, 1990

7/479911

Chingshun Cheng - Austin TX
Scott L. Porter - Austin TX
William C. Richardson - Round Rock TX
Paul J. Roy - Round Rock TX

International Business Machines Corporation - Armonk NY

G11C 2900

395575

A system and method is provided for testing a computer system main memory during system startup. An initial block of memory is tested and marked as valid or invalid during a startup sequence, with the remaining system memory initially marked as bad. An operating system and applications can be loaded into the initial block and operate normally, and a concurrent process is invoked to test the remaining system memory. This allows the remaining system memory to be tested and marked as valid during normal system operation.

53575210, Oct 18, 1994

Mar 10, 1993

8/033066

Chingshun Cheng - Austin TX
Paul J. Roy - Round Rock TX

International Business Machines Corporation - Armonk NY

G11C 2900

371 213

A method for testing directly addressable memory in a computer system uses address sensitive test data. When a memory error occurs, or when an initial testing of the memory indicates an error, the affected locations are retested with selected address sensitive memory test patterns. Proper address sensitive pattern selection allows all of the data bits, ECC data bits and address parity bits to be tested.