Apple performa 400 series サービスマニュアル

 

 Troubleshooting

Symptom Charts/Built-in Video - 5

 

Vertical lines, 

horizontal lines, or 

snow appears on 

screen, or screen is 

completely dark; 

startup tone is 

normal

1 Replace video cable.

2 Replace monitor.

3 Replace VRAM SIMM.  Refer to Hardware/Memory

4 Replace logic board. Retain customer’s SIMMs.

5 Replace power supply.