Dirty Power

GeoMoon5 · 09-28-2009, 05:00 PM

How do I test my PSUs to make sure they are outputting clean power?

I suspect my PSU was outputting dirty power. There was faint banding flowing from the top to bottom, or from the bottom to top of my screen (Dell flat-screen). The effect made me think of what might happen if a fan was making the power dirty. The only way I was able to fix the problem initially was to use my DVI port instead of my VGA port. When I switched out the power supply with another one, the problem went away and I was able to go back to the VGA port. Luckily, it appears the motherboard and other components were not damaged.

How do I test my PSUs in the future to make sure they are outputting clean power? I never even knew that needed to be tested. The PSU tutorials don't seem to mention it either. Maybe I missed it. I wonder what else should be tested with a PSU that isn't mentioned. Those little testers seem to only test voltages and not more complicated stuff like clean/dirty power.

After I turn off my computer, I turn the power off via my power strip to save electricity. Could that damage the PSU in some way over time?

Any help would be appreciated. I have some really old PSUs running some computers (one PSU is well over 10 years old) and I would like to be able to run a full test on them to make sure they're still fully operational. I read that the normal life span of a PSU is 3 to 5 years. Thus, I'm concerned.

Thank you in advance for any help! =D

Phædrus2401 · 09-28-2009, 07:20 PM

You can view the actual voltages the PSU is delivering via the hardware monitoring section in the BIOS.

As for determining electrical noise levels, I think you'd need an oscilloscope for that.

**greenbrucelee** · 09-28-2009, 11:42 PM

you can also test it with a multimeter by putting the multimeter probes into the + and - sections on the 24 pin ATX connection on the mobo.

**speedster123** · 09-29-2009, 05:08 AM

You might alleviate your concerns by installing quality power supplies before the outdated units ruin your components. Eventually they will fail and/or start fluctuating.

**Tyree** · 09-29-2009, 07:50 AM

Quote:

Originally Posted by speedster123

You might alleviate your concerns by installing quality power supplies before the outdated units ruin your components. Eventually they will fail and/or start fluctuating.

Best solution.

09-28-2009, 05:00 PM	#1 (permalink)
GeoMoon5 Registered User Join Date: Sep 2008 Location: California, United States Posts: 14 OS: XP sp3	Dirty Power How do I test my PSUs to make sure they are outputting clean power? I suspect my PSU was outputting dirty power. There was faint banding flowing from the top to bottom, or from the bottom to top of my screen (Dell flat-screen). The effect made me think of what might happen if a fan was making the power dirty. The only way I was able to fix the problem initially was to use my DVI port instead of my VGA port. When I switched out the power supply with another one, the problem went away and I was able to go back to the VGA port. Luckily, it appears the motherboard and other components were not damaged. How do I test my PSUs in the future to make sure they are outputting clean power? I never even knew that needed to be tested. The PSU tutorials don't seem to mention it either. Maybe I missed it. I wonder what else should be tested with a PSU that isn't mentioned. Those little testers seem to only test voltages and not more complicated stuff like clean/dirty power. After I turn off my computer, I turn the power off via my power strip to save electricity. Could that damage the PSU in some way over time? Any help would be appreciated. I have some really old PSUs running some computers (one PSU is well over 10 years old) and I would like to be able to run a full test on them to make sure they're still fully operational. I read that the normal life span of a PSU is 3 to 5 years. Thus, I'm concerned. Thank you in advance for any help! =D Last edited by GeoMoon5; 09-28-2009 at 05:15 PM.

09-28-2009, 07:20 PM	#2 (permalink)
Phædrus2401 Hardware Tech Team Join Date: Mar 2009 Location: New Orleans Posts: 3,821 OS: Vista Ultimate x64 SP1 + Ubuntu 9.04 My System	Re: Dirty Power You can view the actual voltages the PSU is delivering via the hardware monitoring section in the BIOS. As for determining electrical noise levels, I think you'd need an oscilloscope for that. __________________ Good PSU brands: Corsair, SeaSonic, CWT, PC Power and Cooling, Thermaltake Toughpower, CoolerMaster Real Power Pro On 80+ Certification - PSU Information and Selection - Power Supply Myths You don't get what you don't pay for.

09-28-2009, 11:42 PM	#3 (permalink)
greenbrucelee Mentor Hardware team Join Date: Apr 2007 Posts: 1,853 OS: XP SP3 My System	Re: Dirty Power you can also test it with a multimeter by putting the multimeter probes into the + and - sections on the 24 pin ATX connection on the mobo. __________________ Microsoft certified professional, Network +, A+ certified

09-29-2009, 05:08 AM	#4 (permalink)
speedster123 Mentor Join Date: Oct 2006 Location: United States-New York-Long Island Posts: 5,223 OS: xp pro SP3	Re: Dirty Power You might alleviate your concerns by installing quality power supplies before the outdated units ruin your components. Eventually they will fail and/or start fluctuating. __________________