Toshiba QOSMIO G20 manual Memory Test Tests and Diagnostics

3.8 Memory Test 3 Tests and Diagnostics

3.8Memory Test

To execute the Memory Test, select 2 from the DIAGNOSTIC TEST MENU, press Enter and follow the directions on the screen. Move the highlight bar to the subtest you want to execute and press Enter.

Subtest 01 Conventional memory

This subtest writes a constant data to conventional memory (0 to 640 KB), then reads the new data and compares the result with the original data.

Subtest 02 Protected Mode

NOTE: The CONFIG.SYS file must be configured without expanded memory manager programs such as EMM386.EXE, EMM386.SYS or QEMM386.SYS. Also, the HIMEM.SYS must be deleted from the CONFIG.SYS file.

	This subtest writes constant data and address data (from 1MB to maximum
	MB), and reads the new data and compares the result with the original data.
Subtest 03	Protected Mode (Cache off)
	This subtest executes the same way as the subtest 02 with the cache off.
Subtest 04	Cache Memory
	To test the cache memory, a pass-through write-read comparison of ‘5Ah’
	data is run repeatedly to the test area (‘7000’:’Program’ size to ‘7000’:’7FFF’
	(32 KB)) to check the hit-miss ratio (on/off status) for CPU cache memory.
	One test takes 3 seconds.
	Number of misses < Number of hits → OK
	Number of misses ≥ Number of hits → Fail
Subtest 05	Stress
	Data (from 1MB to the maximum MB) is written from the 16KB write buffer
	to the 16KB read buffer and compared the data in the buffers. The read buffer
	starts from 0001 and the comparison is continued with the following read
	buffer addresses: 0001, 0003, 0005, 0007, 0009, 000b, 000d and 000f.

3-24 [CONFIDENTIAL] QOSMIO G20 Maintenance Manual (960-511)