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On 22/08/2015 21:19, Alan Grimes wrote: |
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> Isn't this the filthiest oscilloscope u've seen recently? |
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I've seen cleaner. And dirtier. |
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> The only bare metal contact that I could safely use to get a reading off |
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> was a +12v line on a spare PCI-E gpu plug. The ground reference is the |
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> chassis. |
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> |
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> You can see the machine's settings in the photo clearly enough. The |
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> waveform is fairly constant, it stays in this mode most of the time but |
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> sometimes goes into a "low ripple" mode where the ripple falls to +/- |
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> 20mv and holds tight. The scaling indicates the upward spikes are around |
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> 0.120 volts and the downward spikes are about 0.22 volts. This |
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> __SHOULD__ be within the input tolerances of the motherboard's regulators. |
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> |
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> I would call this PSU marginal, it absolutely does power the machine but |
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> it's noise output is a bit larger than what I would prefer. |
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I would call that PSU on it's last legs, and highly likely to be the |
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root cause for the recent difficulties you've posted about and possibly |
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more too. +100mV/-200mV is excessive |
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> Given that i'm flat on my ass broke with a foreclosure over my head, I |
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> am powerfully inclined to continue to live with the PSU the way it is |
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> now until it is no longer possible to do so. |
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Well now you put it that way, you don't have many options other than use |
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what you've got. |
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But do realise that the next time you run into some weird issue, that |
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PSU is most likely what you are dealing with as root cause. |
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> I had to use my windows 7 machine to get the photo off my camera because |
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> digikam does not compile. =| |
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-- |
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Alan McKinnon |
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alan.mckinnon@×××××.com |
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