On Sunday 23 Aug 2015 01:11:03 Fernando Rodriguez wrote: > On Saturday, August 22, 2015 3:19:50 PM Alan Grimes wrote: > > Isn't this the filthiest oscilloscope u've seen recently? > > > > The only bare metal contact that I could safely use to get a reading off > > was a +12v line on a spare PCI-E gpu plug. The ground reference is the > > chassis. > > > > You can see the machine's settings in the photo clearly enough. The > > waveform is fairly constant, it stays in this mode most of the time but > > sometimes goes into a "low ripple" mode where the ripple falls to +/- > > 20mv and holds tight. The scaling indicates the upward spikes are around > > 0.120 volts and the downward spikes are about 0.22 volts. This > > __SHOULD__ be within the input tolerances of the motherboard's > > regulators. > > Regulators don't filter noise, they introduce it. Capacitors do that as > somebody pointed on the other thread. > > So if you're on a tight budget and you have an electronics surplus store > nearby you can replace all the capacitors on your mobo and PSU (except the > big bulky ones on the PSU) for about $3.
It is quite likely that only the secondary circuit on the PSU needs to have its electrolytic capacitors replaced. We're talking of anything between one to half a dozen of capacitors. In all likelihood less than a $1 to $3. If any are even slightly domed I'd start with those and spend no more than a few cents. Primary circuit ceramic capacitors (transient protection) could have been affected if the PSU was submitted to high surges in the mains supply. I had one go bad on me after sheet lightning hit the area once. Its replacement along with a resistor fixed the PSU without any further problems and to much of my surprise - I thought it was a gonner! Domed capacitors on the MoBo is a different story. Quite likely other components would have been affected and many of them are surface mounted. You'll need a magnifying glass and steady hands for those. It is not something I would attempt in haste, as it is easy to damage more components than what you fix on a MoBo. YMMV. PS. Noisy PSUs are nothing new. The noise is can be caused by the capacitors, or the coils. Although annoying it does not necessarily mean that there is an electrical problem with the components. If the fan is rattling, then a drop of oil on its bearing should soon put a stop to this. As Dale mentioned, a stalled fan will not help the longevity of the remaining components. :-) -- Regards, Mick
signature.asc
Description: This is a digitally signed message part.
