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That 'try unplugging it for 30 seconds' advice actually fixed a tough one
I spent two hours last week on a Dell Optiplex that kept boot looping. Swapped the PSU, tested the RAM, even reflowed the caps. Nothing worked. My buddy Greg who works at a recycling center told me to just hold the power button for 60 seconds with the cord out. I laughed at him but tried it out of desperation. Booted right up after that and has been fine for 7 days now. How does a simple drain of residual power fix something that looks like a hardware failure? Has anyone else seen this actually solve a legit broken feeling problem?
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kimr9110d ago
Dude, that "drain the residual power" trick is way more legit than people give it credit for. I had an old HP laptop that would just black screen on boot, no POST, no nothing. I tried everything, even ordered a new mobo. Then I saw a forum post about holding the power button for 60 seconds after unplugging the battery and the charger. Did it and it booted like nothing was wrong. The caps in modern boards hold a charge for a long time, and if some chip gets into a weird state from that stored energy, it just hangs forever. Pulling the cord and draining it resets the power management controller, clears the BIOS glitch, or whatever. It's like a full brain reboot for the motherboard. It wont fix a dead PSU or a blown mosfet, but for those weird lockups that look like a hardware death, it works more often than youd think. That 30 second thing is the "have you tried turning it off and on again" for deep hardware issues.
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kai_ramirez3810d ago
The real trick there is doing it with the CMOS battery out too.
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Jumping in here to gently nudge you on one thing - the 60 second hold vs 30 second unplug thing. It's not about the caps holding a charge for the whole 60 seconds, they drain way faster than that. What really happens is you're forcing the PSU's capacitors to fully discharge through the motherboard's power rails, which resets any weird latch states in the voltage regulators and the PCH. I've had a Gigabyte board that would get stuck in a boot loop after a brownout and nothing worked until I pulled the cord and held the power button for a solid 45 seconds. The 30 second unplug is more for letting the CMOS battery's backup voltage stabilize, while the hold the button thing is specifically for draining those big input caps on the main power lines. They're two different problems that look the same.
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