MiTAC 8355 service manual AGP Controller Failure LCD No Display, U9 P6

8355 N/B MAINTENANCE

8.4 AGP Controller Failure LCD No Display

Symptom:

There is no display on LCD although power-on-self-test is passed.

P5

U506

North Bridge

VT8385

U9 P6

ICS950403

PANEL_ID[0:3]

J2

P11

AGP_AD[0:31]

5,6,7,8

AGP_SBA[0:7]

P7

TXCLK+

11

TXCLK-

13

AGP_CBE[0:3]

TX2CLK+

10

TX2CLK-

12

AGP_ST[0:2]

TXOUT[0:3]+

17,23,29,35

AGP_ADSTB[0:1]

TXOUT[0:3]-

19,25,31,37

TX2OUT[0:3]+

16,22,28,34

AGP_ADSTB[0:1]#

TX2OUT[0:3]-

18,24,30,36

AGP_RESET#

R503

F501

L46

120Z/100M +PANEL_VDD 1,2,3

U16

1M

FUSE_1206

ENAVDD

+3V

LCDLCD

AGP_REQ#

C39

R586

R504

1 2 3

1U

AGP_GNT#

0

10K

4

Q503

ATI M10

AGP_PAR

Q501

C505

SI4835DY

AGP_STOP#

2N7002

0.22U

5 6 7 8

AGP_DEVSEL#

+3V

+3V

+5V

AGP_TRDY#

R190

R817

J3

P24

2

AGP_IRDY#

R595

10K

10K

L39

ENABL_VGA 120Z

AGP_FRAME#

0

ENABKL 1

3

1

Q518

AGP_WBF#

DTC144TKA

AGP_RBF#

P23

57 H8_ENABKL

U511

D503

L42

To

R91

22

66M_AGP

H8

45

RLS4148

BLADJ

120Z

4

Inverter

Board

C211

C687

R338

0.1U

1K

22P

X1

X2

R404

C291

0

22P

R403

R139

X3

C290

0

1M

27MHz

22P

132