MiTAC 7521 N - Memory Test Error

101
7521
7521
N/B MAINTENANCE
N/B MAINTENANCE
7.5 MEMORY TEST ERROR
Either on board or extend SDRAM is failure or system hangs up.
U22
SIS
630
SMDATA, SMCLK
U13
ICS9248-102
Clock Synthesizer
MD[0~63]
SDRAMCLK[0~3]
DCLK[2,3]
DCLK[0,1]
MAB#[0~14]
DQMA#[0~7]
CS#[0~3]
SRASA#,SCASA#
CSA#[2,3]
CSA#[0,1]
U509
74LVC244
CKE
R591
8.2K
+S3V
CKE[0,1]
CKE[2,4]
ON BOARD 64MB
SDRAM
U16,U21,U26,U30 U15,U20,U25,U29
J6
RP21,RP24,RP26,RP27
RP39,RP42,RP51,RP50
CSA#[0~3]
RP38
WEA#
144 PIN SODIMM
R181,R167
R185
R139
SDCLK