AlanRatcliffe
Kinda rhetorical though...
Why is it that the PSU will wait until you've gone back in, tidied up all the cables, used multiple ties, tested, put the cover back on, tested again and bolted the whole damn thing into a rack before blowing?
BTW... I've resolved only to use Seasonic PSUs in future. It's just not worth the savings if you have to go back in once a year to replace an "affordable" PSU. Meanwhile my one decent Seasonic PSU is noodling along, quietly and happily driving its third build.
babbalute
I assume you talk PC power supply units ? Always use PSU that are 25% (or more)overrated for the requirement. Rather use two PSU's instead of one big one. There is plenty space in a big PC case to put the second one. Make sure they get good ventilation, the fans are clean and can get rid of the hot air easily. PC cases are usually placed in a corner or in a badly ventilated area. The hot air produced b the PSU cannot removed easily from the surroundings of the PC case and is sometimes sucked back in instead of cooler air. I have mine outside the PC case(I extended the cables which is easily done) Make sure the connections are good between the cable connections and the PC board. Sometimes when pushing in the connectors the connection pins are pushed back and the connection pins have a small contact surface area resulting in a hot spot due to the high current flowing, this will effect the PSU. If you can establish which power supply blows on the PSU that would help. If it is always the same 5V + or - or 12V that indicates that the load is to high on that particular supply. Use a second PSU in that case. You can also use the CPU bios to check voltages ones running if it is available. The actual indicated voltages should be damn close to what it should be. e.g. 5V should give a reading of not less than 4.8V. The current is a bit more difficult to measure but I'm sure you can make a plan there. The to high current demanded is causing the PSU breakdown. As with all electronic gadgets, the PSU is the most important and a better make or brand will last longer.
AlanRatcliffe
Yeah I try run overrated PSUs - the more power headroom there is, the more likely they are to run cooler and quieter.
Strangely enough, the PSU in question blew with the PC turned off. I suspected maybe a board mounted fuse, but it was way more catastrophic than that, with an IC blowing it's top and one leg clean off and a resistor with a missing leg. Just reached it's MTBF, I suppose...
I'm a bit of a nut with getting efficient cooling, big heatsinks and fans where possible, but airflow is generally relatively low, as I do tend to compromise in favour of keeping the noise down (my work PC generates nothing more than a little hard drive seek noise and I'm aiming for similar with this unit). The case in question is more than a little cramped though as it's a 4U rack chassis (Carillon).
It is running a bit hot and noisy ATM as I've yet to replace the stock cooler for something better that fits the case (I've been trying to source a Noctua cooler locally, but the agents don't import the one I want). The PSU (both the one I put in and the stock I just put back) has a big bottom mounted fan, so helps pull air over the CPU, which means it gets hotter air at its intake - but with space for only one 80mm case fan, I don't really have much choice