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| Thread ID: 132671 | 2013-05-18 23:22:00 | PSU recommendations? | Tony (4941) | Press F1 |
| Post ID | Timestamp | Content | User | ||
| 1341871 | 2013-05-18 23:22:00 | It looks like the PSU on my main PC has died. I press the on button and nothing happens - no fans, nothing. There is an LED lit on the mobo, but nothing else. It could be the switch I guess, but I'm suspecting the PSU. So I'm looking for recommendations for a replacement. The dead one is a Q Technologies 560w ATX, and I'd be looking for a similar spec - good make, quiet, 600-ish watts. One with modular cables that you can plug in would be good, but not vital. Any suggestions? |
Tony (4941) | ||
| 1341872 | 2013-05-18 23:45:00 | What about these (quietpc.co.nz) ones? | Tony (4941) | ||
| 1341873 | 2013-05-19 01:48:00 | If the motherboard has an LED going then the PSU is at least working up to the point of providing the 5v Standby rail. It could well be the motherboard, button or PSU that's faulty - or even some other part. Those Zalman PSUs look OK on paper, but I don't know what the quality is like. They are entry-level models so I wouldn't expect them to be awesome in terms of longevity. |
Agent_24 (57) | ||
| 1341874 | 2013-05-19 04:19:00 | It can be risky but if you have a steady hand on the 24 pin plug from the psu to the motherboard you can use a piece of wire to short the green wire to one of the black ones, this should power up the PSU and helps prove where the fault is. Always safest of course if possible to test by swapping with known good parts rather than do this sort of thing. |
dugimodo (138) | ||
| 1341875 | 2013-05-19 04:23:00 | OK, thanks for that. So it might be a good idea to get it checked out before I fork out for a PSU? If the mobo was stuffed, I would have thought that at least the fans might have powered up, even if they immediately died - or is that not true? Is there anything I can do with limited hardware knowledge or diagnostic gear to narrow the possibilities? I do have another PC with an ATX PSU, but I don't want to dismantle 2 PCs if I can avoid it. | Tony (4941) | ||
| 1341876 | 2013-05-19 04:25:00 | It can be risky but if you have a steady hand on the 24 pin plug from the psu to the motherboard you can use a piece of wire to short the green wire to one of the black ones, this should power up the PSU and helps prove where the fault is.That idea does make me a little nervous - I have visions of a flash of light and a puff of smoke and a totally fried machine :( | Tony (4941) | ||
| 1341877 | 2013-05-19 04:41:00 | Is there anything I can do with limited hardware knowledge or diagnostic gear to narrow the possibilities? I do have another PC with an ATX PSU, but I don't want to dismantle 2 PCs if I can avoid it. If you have a known working PSU then swapping them would be a good start. Alternatively you could try the manual power on method as dugimodo suggested, although I would first try doing this with the PSU completely disconnected from all other hardware. If the PSU is faulty, and you force it to power up, it could ruin something. |
Agent_24 (57) | ||
| 1341878 | 2013-05-19 05:23:00 | So if I do try the mission impossible approach (green wire! black wire! - which?) then what would I expect to happen if the PSU is working, and what if it is faulty? | Tony (4941) | ||
| 1341879 | 2013-05-19 05:40:00 | Short the green wire (PS_ON) to any of the black (GND) ones (ie: pull it low) If it's working OK it should turn on; the fan will start spinning, any lights will come on. You can verify the voltages are sensible if you have a multimeter etc. If it is faulty, it may not power on at all, or power on and then turn off quickly (note: this can also happen if it has no load), or power on with incorrect voltages, or blow up (unlikely, if that didn't already happen). If the thing does appear to start OK, you could try again with it actually hooked up to the motherboard. You might also like to try swapping the power button with the reset button in case the power button has broken and nothing else is wrong. (Or just shorting out the power button pins with a screwdriver or such, but just using the other button is safer, so you don't miss) |
Agent_24 (57) | ||
| 1341880 | 2013-05-19 05:55:00 | OK, thanks. I think I'll try swapping the start and reset switches initially. If it still doesn't work, I would think it is much more likely to be the PSU rather than the mobo? I don't have any test equipment (I'm not a hardware/electrical person at that level), I'll bite the bullet and swap out the PSU for the one from my other PC and see what happens. | Tony (4941) | ||
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