<div dir='auto'>Thank you for the suggestion! Tried with a modern be quiet power supply, but identical results sadly.<div dir="auto"><br></div><div dir="auto">- HP</div></div><div class="gmail_extra"><br><div class="gmail_quote">On 9 Dec 2025 21:28, Jonathan Katz via rescue <rescue@sunhelp.org> wrote:<br type="attribution" /><br><br><!DOCTYPE HTML PUBLIC "-//W3C//DTD HTML 3.2//EN">
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I would start by testing the power supplies and making sure they<br>
output the correct voltages on the right pins. These power supplies<br>
are almost 30 years old (Ultra 5/10 are circa 1997-1998) --<br>
<br>
I vaguely remember that these systems can take a standard ATX supply,<br>
so you may want to use one of those to test the boards (double check<br>
the FEH.)<br>
<br>
Then it's all the standard idprom stuff.<br>
<br>
On Tue, Dec 9, 2025 at 8:20\u202fPM HP van Braam via rescue<br>
<rescue@sunhelp.org> wrote:<br>
><br>
> Hello!<br>
><br>
> I have two Sun Ultra 10s with the same fault, and they came to get the same fault in the same way.<br>
><br>
> They both did the following:<br>
><br>
> * Started to get IDProm errors<br>
> * Used the "normal" instructions for fixing this<br>
> * Some time later after a reboot things started to go wrong<br>
><br>
> This sort of worked for a moment, but now when I apply power to either machine the power led stays off (most of the time) in the very rares time when the power led does turn on I can't succesfully boot the machines. Sometimes they end up booting into Solaris but they are not stable.<br>
><br>
> For instance even dtlogin will just start and cycle on and off until ultimately the system hangs entirely. At this point pressing stop+a and resetting usually doesn't boot correctly.<br>
><br>
> Swapping around ram/CPUs/power supplies between the two systems has no effect. Removing the AFB doesn't really seem to change anything either.<br>
><br>
> It seems kind of unlikely that both computers have the same obscure hardware fault in the same component, I hope this is all just the IDProm fucking up.<br>
><br>
> I tried both of the IDProm chips in my minipro reader and they seem to not really read that same each time. And writing data to the chips doesn't seem to "stick".<br>
><br>
> Help would be very much appreciated! Thank you!<br>
><br>
> - HP<br>
> _______________________________________________<br>
> rescue list - http://sunhelp.org/mailman/listinfo/rescue_sunhelp.org<br>
<br>
<br>
<br>
-- <br>
-Jon<br>
+44 7792 149029<br>
<br>
_______________________________________________<br>
rescue list - http://sunhelp.org/mailman/listinfo/rescue_sunhelp.org<br>
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