102
7521
7521
N/B MAINTENANCE
N/B MAINTENANCE
7.5 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. (
J6
)
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:
U22, U13
U15, U16
U20, U21
U25, U26
U29, U30
RP21, RP24
RP26, RP27
RP39, RP42
RP51, RP50
RP38, J6, U509
Signals:
MDR[0~63]
MD[0~63]
MAB#[0~9]
MAB[10,13]
MAB#[11,12]
SCASA#,
SRASA#
WEA#
DQMA#[0:7]
CSA#[0:3]
CKE[0:3]
SDRAMCLK[0:3]
SMBDATA
SMBCLK
Either on board or extend SDRAM is failure or system hangs up.
