Two cases of computer black screen with "substitution method" "control method"--Hardware maintenance

"Substitution" is a way to find or troubleshoot a failure by replacing a part that may be faulty or without fault, but not working properly. The "control method" is to compare the faulty computer or component with a computer or component that does not have a fault, to find out the method of troubleshooting. Both of these methods are useful, and they are used in many troubleshooting of the computer. This is my computer room in the maintenance of the two magic weapons, the following two special examples, I hope to give you a little enlightenment.

Fault One

Unit new buy back a 14-inch display, the specification said the highest resolution for 1024x68, so I will change the resolution to 1024x768, restart the machine, black screen. 

Failure reason: Can determine, this monitor actually achieves the resolution and the specification nominal resolution does not match, this monitor damage possibility is very small, the biggest possibility is the resolution does not have the 1024x768 and does not light.

Solution: Use the "substitution method" to solve the problem. Find a monitor that can go up to 1024x768 resolution, replace the new monitor, and then change the resolution back to the range that the new monitor can use, and then switch back to the new monitor.

Fault Two

A diskless WIN95 workstation, one day boot, black screen, restart several times, the fault is still, the initial judgment is that the monitor is bad or the system is bad.

Solution: Or the first use of "replacement" to find fault location, the standby display in exchange, restart the machine, Blue sky, the word on the desktop than the original number of times, can be judged to be the fault of the monitor. Although the fault found, but also have to change back to the font: Right click on the desktop, choose "Properties", bad! How can only display the property dialog box about One-fourth, fortunately, the dialog box can move, but how can not see the part to be modified. What to do? It seems to have to use the "control method" to compare operations, hurriedly open a same machine without fault, on the machine above the operation of a step, and then return to the fault machine operation one step, so several steps, and then restart, haha! Troubleshooting. And then put on the original monitor, incredibly normal use.

Failure reason: This is a student public machine, must have the student to define the font too big, the original monitor quality is not good, causes the original monitor not to display normally and the black screen.

The above fault, many people may never encounter, but the method of troubleshooting is really practical and effective, perhaps many people will use.