97
M722 N/B MAINTENANCE
M722 N/B MAINTENANCE
6.4 MEMORY TEST ERROR
MEMORY TEST ERROR
1. Check if on board SDRAM chips are no cold
solder.
2. Check the extend SDRAM module is installed
properly. (
J502
)
3. Confirm the SDRAM socket is ok, no band
pins.
Test
OK?
NO
Try another known good
SDRAM modules.
END
YES
NO
Replace mother
board or into
board level
Troubleshooting.
Test
OK?
Correct it.
YES
Board-level
Troubleshooting for
Memory test error.
Check the following parts for cold solder or one of the following
parts on the mother-board may be defective, use an oscilloscope
to check the following signal or replace the parts one at a time and
test after each replacement.
Parts:
U3~U6, U510
U503~U505
U508,RP23
RP20, RP13
RP503, RP27
RP22, RP14
RP504, J502
Signals:
MD[0:63]
D_MD[0:63]
MA#[0:9]
MA10,MA13
MA#[11,12]
SCAS#, SRAS#
MWEA#
DQMA[0:7]
CS#[0:3]
CKE[0:3]
SDRAMCLK[0:2]
SMBDATA
SMBCLK
Either on board or extend SDRAM is failure or system hangs up.