Repair of Sotay GTX550Ti display card

Repair of Sotay GTX550Ti display card.

The display card of Sotay GTX550Ti does not display, and the resistance short-circuit is directly put into operation, and the repair is finished.

Machine model: Sotay GTX550Ti.

Fault phenomenon: the display card does not display and the chip element is defective.

Maintenance process: get the video card to check that the chip components have some defects. Several Capacitor of PCI bus has been dropped. Find a piece of waste display card and transplant several Capacitor. After completing the Capacitor, several groups of VCC diode value are basically normal, and then test several groups of VCC.

Repair of Sotay GTX550Ti display card Figure 1.

VCC.075,VCC.071.071.071.075.

Repair of Sotay GTX550Ti display card Figure 2.

Repair of Sotay GTX550Ti display card Figure 3.

Repair of Sotay GTX550Ti display card Figure 4.

Through the above VCC, it is concluded that there is no VCC in the core of the core graphics card, and there is no waveform in the driving of the upper and lower tubes with an oscilloscope. It is suspected that the PWM chip is not working.

Repair of Sotay GTX550Ti display card Figure 5.

Repair of Sotay GTX550Ti display card Figure 6.

The VC discharge of M chip is 11.8V, which is normal.

Repair of Sotay GTX550Ti display card Figure 7.

Check that VCC is 0V, and VCC is not turned on.

Repair of Sotay GTX550Ti display card Figure 8.

When running the circuit to a resistor with a small copper brush, it is found that there is 3.2V at one end of the resistor and 0V at the other end of the resistor.