Question Problem regarding Cooler Master 800W Silent Pro GOLD

[Navin Talati]

I have a Cooler Master 800W Silent Pro GOLD power supply unit in my system. Some times it happens that I do not get the display in my monitor. I have checked Voltages at each and every wires in looms of the PSU connecting to MoBo, CPU and HDD/ODD/SSD etc. All voltage like 12V, 5V, 3.5V etc. are ok.
When I replace it with other PSU of other brand, the system works normally.
Some one told me that it happens due to the insufficient voltage supply to CPU. on the motherboard. The MoBo in my system is Asus M4A88T-M and it has 4 point connection for CPU from motherboard. I am also told that let it show 12 V when measured externally but while running of the system sometimes in the way it may drop the Voltage and so the system malfunctions.

I seek guidance and help for following:

What may be the fault in PSU?
How could it be resolved?
How the PSU could be checked and repaired?

Regards to all and thanks in anticipation.

 

[Murissokah]

Keep in mind electronic loads are very dynamic and they affect the power supply, so you won't be able to tell if the PSU is within parameter by simply measuring voltages on its pins. You would need to hook it up to an osciloscope and check how the voltages behave during transitions (overshoots, voltage drops, transition times, etc). I assume you don't have an osciloscope at home.

Voltage drops under load are easier to understand, as they are more intuitive. The power supply can't sustain that much power, so voltage drops. But this often makes people confused as to how it would happen when the PSU is rated much higher than what is required by the hardware (like the 800W on your PSU). And the answer here is that voltage drops are not the only way things can go wrong. Sometimes the very logic used to compensate for drops causes voltage overshoots that exceed parameters. And there are other issues like cross-contamination (load condition on one part of the PSU affecting output elsewhere), harmonics and other power quality characteristcs that may cause problems.

If this sounds complicated it's beacause it's not supposed to be a problem for the consumer to solve. Which is why I don't recommend trying to fix power supplies unless they blew a capacitor or some other obvious issue like that. Sometimes a Power Supply is a bad match for a certain load, you might put this PSU in a different PC and it may work for 10 years with no issues.

Finally, fixing an intermittent problem in a power supply can be a pain in the ass. I've dealt with one for 2 years because I didn't want to let go of a 1200W PSU that had cost me a large sum. In the end it was just 2 years of unecessary fiddling until I finally replaced it with a much cheaper one and never had an issue since.

 

[DSzymborski]

I have a Cooler Master 800W Silent Pro GOLD power supply unit in my system. Some times it happens that I do not get the display in my monitor. I have checked Voltages at each and every wires in looms of the PSU connecting to MoBo, CPU and HDD/ODD/SSD etc. All voltage like 12V, 5V, 3.5V etc. are ok.
When I replace it with other PSU of other brand, the system works normally.
Some one told me that it happens due to the insufficient voltage supply to CPU. on the motherboard. The MoBo in my system is Asus M4A88T-M and it has 4 point connection for CPU from motherboard. I am also told that let it show 12 V when measured externally but while running of the system sometimes in the way it may drop the Voltage and so the system malfunctions.

I seek guidance and help for following:

What may be the fault in PSU?
How could it be resolved?
How the PSU could be checked and repaired?

Regards to all and thanks in anticipation.

What are the rest of the specs? It's important.

Also, simply using a multimeter doesn't really tell you all that much except very basic information about how the PSU is working. To actually directly test a PSU, you really need a proper load tester and oscilloscope. This was a decent, though not top tier, unit at the time, but it's quite old now.