Thanks @robespierre for the detailed explanation of the R44’s intended role and its scorching hot operational nature.
With the latter in mind perhaps as Jacques intimated, its location and close proximity to that sub-board and especially to C29, with less than adequate heat shielding (if any at all) it could possibly have contributed greatly to the baking, swelling and possible failure of that single capacitor over time. And with that in mind… somewhat a poor design referring to the PSU’s internal layout and lack of heat shielding?
The black rubber / composite(?) shroud noted here above on Jacques’ R44 was nearly 75% degraded (melted away) on mine and perhaps more interesting… is that the PSU continued to function for six months before total failure, after I had supplied supplemental power directly to the PSU fan from an independent outside power source. The fan had stopped working beforehand. Perhaps the damage had already been done.
Also, given the scorching hot nature… also perhaps a contributor to why my R44 seemed to have a loose, poor solder joint? Weakened perhaps over countless working hours and at those scorching temps?
If you always have 12 VDC consumers attached you can just cut the resistor out.
You’re not suggesting that by not having the 12 VDC demand of a conventional hard drive alone present, that this could lead to the eventual failure of R44 and the PSU? Especially when considering all other 12V demands on the PSU (like mobo, other internal 12V components and the case fan, etc.)? Or, just a warning about powering on a PSU outside of the machine, unloaded?
If the former - then perhaps that does not bode well for SSDs, mSATA and/or other likewise “power-adapted” storage media actually requiring less than 12 VDC?
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