Am I experiencing an unacceptable amount of power ripple

[J3anyus]

Alright, I'm having a few minor crashes every so often, however, I believe that they're due to software issues. Either way, I got to thinking and was wondering if maybe they're being caused by power ripple, which I've heard can damage components and cause huge instability issues on machines. So, just for fun, I pulled out my multimeter and ran some tests.

While idling at the Windows desktop, my PS is putting out the following voltages:

+5V - 4.96V
+12V - 11.94V

As long as I'm idling, my multimeter is unable to detect any ripple. I loaded up 3DMark03 and started copying a bunch of large files between drives, and saw my voltages move a little. My +5V stayed pretty steady, and fluctuated very little. Every so often, it would move around a bit, and was always in between 4.93V and 4.96V. My +12V rail was a little bit more jumpy, and was moving around a bit. The +12V rail was always in between 11.82V and 11.94V. It wasn't going crazy or anything, but as I put load on my machine, it gradually moved down to 11.82V, and as I let up on the load, it gradually went back up. When I say gradually, I mean it took about 10-15 seconds to get from 11.94V to 11.82V.

So, here's my question: Is this amount of power ripple enough that it could be causing problems in my machine? I'm not just talking instability, is it likely that this will eventually damage my components? All the voltages are staying within spec, but I know ripple can be very detrimental, even if the voltages are within spec.

Any help would be much appreciated, as I'm thinking about going out and getting a better power supply to throw into this machine. Also, machine specs (it's not posted in my rigs):

2.8GHz P4 C
Intel 865PE reference board
800MHz FSB
300W PS (I'm looking at upgrading to a 430W Antec TruePower)
256MB DDR400
ATI Radeon 9800 Pro
48X Lite-On CD-RW
16X Pioneer DVD-ROM
60GB 5400RPM WD HDD
80GB 7200RPM Maxtor HDD
Turtle Beach Santa Cruz
56K Modem
Onboard NIC

Thanks again!

- Jacob

 

[Bleep]

I think you have some terms messed up. Ripple is the AC component that may be on the DC line. What you are talking about is Voltage Fluctuation and in that respect I dont see a problem.

Bleep

 

[J3anyus]

Originally posted by: Bleep
I think you have some terms messed up. Ripple is the AC component that may be on the DC line. What you are talking about is Voltage Fluctuation and in that respect I dont see a problem.

Bleep

Aha...I could've sworn I saw an article on the AT front page at some point in time that reviewed power supplies and used the term "ripple" to refer to voltage fluctation. Lemme see if I can dig it up...

Edit: Here's the article

http://www.anandtech.com/showdoc.html?i=1774&p=8

Quote from the article:

The ripple is the variation in voltage over a particular rail. Like we mentioned on the previous page, too much fluxuation in voltage can lead to damaged hardware.

Not arguing with you, just letting you know that it's the term the front page used, that's why I used it.

Anyway, anyone else have any opinions? I'm just curious.

 

[J3anyus]

Bump.

 

[redhatlinux]

Bleep has the correct terminology, and BOTH fluctuation and ripple can affect your system if they are out of spec. As stated, ripple is a small AC component on a DC voltage. Fluctuation is a voltage variance (usually under load). Your multi-meter will not see ripple, got to have an oscilloscope. IIRC 10% fluctuation on the +12v is normal, +5 and +3.3 should be tighter, closer to 5%.

 

[FishTankX]

Originally posted by: redhatlinux
Bleep has the correct terminology, and BOTH fluctuation and ripple can affect your system if they are out of spec. As stated, ripple is a small AC component on a DC voltage. Fluctuation is a voltage variance (usually under load). Your multi-meter will not see ripple, got to have an oscilloscope. IIRC 10% fluctuation on the +12v is normal, +5 and +3.3 should be tighter, closer to 5%.

Yes. The Entire ATX specification calls for tollerance of up to 10% fluxes.