On 22/08/2015 21:19, Alan Grimes wrote: > Isn't this the filthiest oscilloscope u've seen recently?
I've seen cleaner. And dirtier. > 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. > > I would call this PSU marginal, it absolutely does power the machine but > it's noise output is a bit larger than what I would prefer. I would call that PSU on it's last legs, and highly likely to be the root cause for the recent difficulties you've posted about and possibly more too. +100mV/-200mV is excessive > Given that i'm flat on my ass broke with a foreclosure over my head, I > am powerfully inclined to continue to live with the PSU the way it is > now until it is no longer possible to do so. Well now you put it that way, you don't have many options other than use what you've got. But do realise that the next time you run into some weird issue, that PSU is most likely what you are dealing with as root cause. > I had to use my windows 7 machine to get the photo off my camera because > digikam does not compile. =| -- Alan McKinnon [email protected]
