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Harrison
30th September 2009, 15:57
In the past year I've repaired a few PCs where the PSU was found to be faulty and needed replacing.

While PSUs are always one of the first thing to check when a PC is acting up, I've not seen this level of PSU failure before when repairing systems. Has anyone else been noticing PSUs don't seem to be as good quality these days?

Some of the PSUs were just dead, or not supplying the correct/any voltages on some of their rails. However, a number of the PSUs have exhibited similar behaviour. When power is supplied to the PSU its fan starts to spin up. This happens even when the PSU isn't installed and is just connected to the power on its own. Does anyone know what could cause this fault?

I even have one PSU that is doing this, with the fan spinning if receiving power, and it has its own standby/power on LED which correctly shows orange when in standby, but with the fan spinning, and goes green when the soft boot pins are shorted, and it seems to be supplying the correct outputs to all rails. It however doesn't power up a motherboard. So that one is a bit of mystery.

It seems to be getting harder to actually find a new PSU that will actually last more than a couple of years. Some of my old systems have PSUs that have been running since new. One is now 11 years old! I wouldn't expect that from any PSUs I buy now.

Kin Hell
30th September 2009, 18:19
<snip> When power is supplied to the PSU its fan starts to spin up. This happens even when the PSU isn't installed and is just connected to the power on its own. Does anyone know what could cause this fault?

Yeah. Every cheap nasy PSU does this if it isn't a switching PSU.

Another symptom is plugging a Power chord into a fully built PeeCee's PSU. All the fans twitch as the PSU gets power, but then you still need to press the "on" button to fire the rig up. - Nasty ass cr4p tbh.

More & more PSU makers are turning towards single Railed PSU's too & as most things in life, cheap components just don't measure up. It's still a case of you pay for what you get.

Kin