Re: Odd PSU problem

On 9/28/20 2:08 PM, Paul wrote:
> philo wrote:
>> Had a power supply die, so I replaced it with a used one I had that I 
>> had marked "good."
>>
>> It booted to the bios and I just set if for default but it never 
>> loaded the OS. It just returned to the bios.
>>
>> HD was detected and set for first boot option.
>>
>> Though I was sure I had a legacy Win10 install, I did try UEFI but 
>> still could not get past bios.
>>
>>
>> Finally a cracked open a new in the box PSU and all worked fine. I 
>> assume there was some low voltage.
>>
>>
>> Both sup[plies went to a metal scavenger
> 
> You could have tried a memtest floppy.
> 
> One of the slightly older single threaded versions.
> 
> Then get out your multimeter and checked supply voltages.
> 
> I suppose Power_Good was signaling a problem.
> 
> I'd probably have the hard drive disconnected while
> working on it at this point. To reduce the chances of
> damaging it. Disconnect power and data.
> 
> Or, you could put a dummy load on the PSU to test it out.
> I have a dummy load, but it is "lite" and hardly a test.
> It's enough though, to tip over my "weak" PSU, which is
> the original Heroichi (HEC) bought for my first PC. It
> hasn't blown up, but that supply can only run one 12V
> fan before that's too much for it. Not enough power
> to run a CPU. That supply is from well before the badcap
> era. Haven't thrown it into the chipper yet.
> 
> I like about 100W for a dummy load. As higher loads cost
> money :-) And my electronics store is gone, so easy access
> to their power resistors is now gone too.
> 
>     Paul



I tossed it so I would not fool around trying to find the problem.

What I really need to do is a get a 24 pin PSU tester


The 20 pin tester is not a good way to test a 24 pin PSU