Question. Power outage due to blowed fuse or turning off psu by switch. Differences?

[lpio211]

Hello. I have an question. Is any difference on impact to pc, when power outage is due to blowed fuse or just simply turning off psu switch. When power outage is due to blowed fuse ,this is the same like when i turn off switch on psu?

 

[VirtualLarry]

It really depends on the waveform, you would have to attach a scope to it and visibly analyze it.

In practical terms, I want to say "mostly", but it's possible for a waveform to be way out of whack before the fuse blows.

 

[Red Squirrel]

Dirty power outages are worse (ex: an unclean power cut where there is a lot of voltage fluctuations before) as the UPS might not pick it up and the computer will get the brunt of it. I've witnessed this happen myself. I've always wanted to monitor that on a scope to see how it looks but I don't have any spare equipment to try it with and don't want to do it with my prod stuff. So in the case of a fuse popping it really depends if it melted very slowly and then arced before cutting power, or if it blew gracefully and cut power cleanly.

This goes for breakers too, if turning off power to a circuit that has computers on it, I always make it a case to throw the breaker fast. A typical breaker is normally internally spring loaded so it's less of an issue but older style cut off switches can be an issue if you turn it off slow.

 

[lpio211]

So i have power cord name: "APC". Psu is Corsair 750 RM.

Few days ago my mother turned on oven in kitchen, and bulb inside oven melted. Fuse of course blown and i got power outage.

This can damage pc?

 

[UsandThem]

Ipio211

This is at least your 5th post about this exact same thing. You need to either get the power in your house fixed, or buy a UPS at a minimum. Yes, unreliable dirty power can damage a PC. Yes, surges can damage a PC. Nobody here can tell you if your PC is damaged. If it doesn't turn on or starts having issues, you'll have to test it when the times comes.

https://forums.anandtech.com/threads/storm-and-lights-dimming-pc-still-on.2521292/#post-39109765

https://forums.anandtech.com/threads/asus-anti-surge-question.2498902/#post-38729835

https://forums.anandtech.com/threads/question-about-asus-anti-surge-was-triggered.2495168/

https://forums.anandtech.com/thread...use-tripped-power-outage-question-pc.2526100/

 

[lpio211]

UsAndThem yeah but for what is psu? I have Corsair 750 RM which have safety features.
I think you are sometimes overthinking, pc components are too not delicate like what you thinking

 

[UsandThem]

UsAndThem yeah but for what is psu? I have Corsair 750 RM which have safety features.

If it has "safety features", why are you even asking these power related questions?

Sudden, abrupt power outages are not good for a computer. Storms and surges are not good for a computer. Dirty power and brownouts are not good for a computer. Yes, quality PSUs have safety features, but they are limited in how they can protect your PC from bad power.

I'm not trying to be rude, but I am trying to get the point across to you about your power issues where you understand and can accept the same answer you always get when posting these questions. Until a moment ago, I even forgot about your monitor / mother cooking post a couple of weeks ago:

https://forums.anandtech.com/thread...ed-to-lower-value-once.2528438/#post-39185319

If you're not willing, or unable to fix the problems that cause your issues, how can anybody on a computer tech forum help you?

 

[UsandThem]

I think you are sometimes overthinking, pc components are too not delicate like what you thinking

Really? Just look at your post history with all your problems you have posted here, and you want to say this to me? Really?

 

[matty67]

A typical surge supression device like a power bar clamps Volta around 330V. Better than nothing but still plenty high enough to cause damage to sensitive components. There are better solutions out there but they're far less common and available. They're also a fair bit pricier than your average power bar but they're whole home systems.

Electronics are the worst things for creating dirty power and we keep adding more and more of them. We're also adding them as sources of power through solar and wind generation. A significant source of dirty power is also coming from the roll out of LED lighting.

Power consumption is generally fairly consistent. How that power is created is in Flux. Volts X Amps = Watts (power)

If you have a drop in voltage current will compensate with an increase. Of you have a spike in voltage the current will drop. Either one can burn out or damage components. The PSU will help protect regulate things but it can only do so much before itself is damaged. Additionally, these spikes are extremely brief. Most people think about the big boom from the overload or short. That's like a massive wrecking ball. A heavyweight fighter connecting on their opponents jaw. The small spikes are an avalanche. Death by 1000000 cuts. Individually a single cut or snowball is harmless, but together they're often worse than that knockout punch.

Sent from my SM-G930W8 using Tapatalk

 

[Billb2]

If you turn off the power switch on you PSU the PSU still supplies 5 volts to the BIOS chip on the motherboard (to retain all the BIOS settings).

If there is a power outage or a fuse blows there is no power to the PSU, and hence, no power to the motherboard's BIOS chip. Then if the BIOS battery is weak, all BIOS settings are lost.

So long as the BIOS battery is good though it makes no difference. The BIOS chip will remain powered.

 

[MrTeal]

If you turn off the power switch on you PSU the PSU still supplies 5 volts to the BIOS chip on the motherboard (to retain all the BIOS settings).

If there is a power outage or a fuse blows there is no power to the PSU, and hence, no power to the motherboard's BIOS chip. Then if the BIOS battery is weak, all BIOS settings are lost.

So long as the BIOS battery is good though it makes no difference. The BIOS chip will remain powered.

This is not true for ATX PSUs. If you turn off the switch on the back of your PSU, it physically disconnects the incoming AC to the PSU. There's no 5Vsb when the power switch is off.

 

[UsandThem]

Just for future posters, there's no need to reply to this thread anymore. Let it slide into necro oblivion.

The OP received everything they needed to fix their issue.

 

[Billb2]

Correct. ATX PSUs do not supply the 5V. but the spec changed about 10 years or so ago to ATX12V

The 24-pin ATX12V 2.x power supply connector

Four wires have special functions:

• PS_ON# (power on) is a signal from the motherboard to the power supply. When the line is connected to ground (by the motherboard), the power supply turns on. It is internally pulled up to +5 V inside the power supply.[2][13]
• PWR_OK ("power good") is an output from the power supply that indicates that its output has stabilized and is ready for use. It remains low for a brief time (100–500 ms) after the PS_ON# signal is pulled low.[14]
• +5 VSB (+5 V standby) supplies power even when the rest of the supply wire lines are off. This can be used to power the circuitry that controls the power-on signal.
• +3.3 V sense should be connected to the +3.3 V on the motherboard or its power connector. This connection allows remote sensing of the voltage drop in the power-supply wiring. Some manufacturers also provided a +5 V sense wire (typically colored pink) connected to one of the red +5 V wires on some models of power supply, however, the inclusion of such wire was a non-standard practice and was never part of any official ATX standard.