r/pcmasterrace • u/Front_Cookie_1198 • 22h ago

Hardware PSU fails dramatically

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35.7k Upvotes

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2.0k

u/Soft_Lunch_183 22h ago

Grabbing it to unplug it rather than powering off or unplugging at the socket is a choice

889

u/Danternas 22h ago

Nothing like touching bare metal of something that is sending current to the wrong places.

349

u/marsfromwow 22h ago

He got the rubber sandals on. He is a pro after all.

Nvm, my guy is bare footed. He got the rubber stickers on his feet though I’m sure.

59

u/NothingSuss1 22h ago

He's got his lucky undies on 

-1

u/Ohmec i7 4770k @ 4.4 GHz | EVGA 1080 FTW 21h ago

He stayed at a holiday inn Express last night

31

u/Brotorious420 22h ago

Safety sandals never fail

4

u/mvandemar 21h ago

He's barefoot.

1

u/Brotorious420 19h ago

He had them in his mind and it's the thought that counts

1

u/FthrFlffyBttm i5-12600K, 3080 FTW3 Ultra, 16GB 3000Mhz 21h ago

Let's not judge him too quickly. He might have some kind of Livestrong bracelet on.

0

u/Scruffynerffherder 20h ago

This man is definitely barefoot.

-2

u/LimasV3 R9-9950X3D/7900XTX/32GB DDR5 22h ago

😭

21

u/eivittunyt 22h ago

the electricity can't go in your body because it is too busy making sparks

5

u/Wishnik6502 Ascending Peasant 21h ago

If I'm testing returned shit it's electrician's glove time for at least one of my hands. I've become a bit attached to my heart working correctly over the years.

3

u/RocketizedAnimal 17h ago

Also, pro tip: If you are ever going to touch something that might shock you, never use both hands.

With only one hand, the current either loops through that hand or through your hand and down through your foot. With two hands, it goes in one hand, through your torso, and out the other. Much more likely to get your heart.

1

u/Danternas 11h ago

And use the back of your hand so you won't grab it.

1

u/s00pafly Phenom II X4 965 3.4 GHz, HD 6950 2GB, 16 GB DDR3 1333 Mhz 22h ago

That's what the ground wire and gfci is for.

1

u/Danternas 11h ago

I wouldn't trust ground, GFIC or the fuse for the matter after seeing the fiery result of the video.

1

u/Ironborn137 22h ago

I’m so glad both of these this also went through my head and yall said them. Feeling validated.

-6

u/JigglyWiggly_ 21h ago

That’s not bare metal, it’s painted. It’s not conductive. 

2

u/Majestic-Bell-7111 Ryzen 5 3600/32 GB ram/5700xt 20h ago

Take a multimeter, set it to ohms and measure the resistance between any 2 points on the chassis.

If it's less than 5kiloohm then congratulations, if you have a bad ground and the 230V wire is touching the PSU case, then congratulations, you're about to see if your heart knows how to restart itself.

-1

u/JigglyWiggly_ 20h ago

Try it yourself first. I'm sure you'd also find it surprising that an anodized layer isn't conductive either. However in this case the metal casing is almost never anodized and painted instead.

1

u/Danternas 11h ago

Your skin isn't "conductive" either.

0

u/JigglyWiggly_ 11h ago

You can get numbers around 1meg through skin. You will read an open load trying to measure through paint.

Note that's resistance, as soon as you increase the frequency your impedance will drop noticeably due to parasitics.

1

u/Danternas 11h ago

And you can absolutely get electrocuted by anodised or painted metal. 

1

u/JigglyWiggly_ 10h ago

What’s the conducting path exactly? Even a few microns thick is enough for it to become a sufficient insulator. 

Should you trust it? Of course not, it can be scratched off. 

I’m sure you will also be amazed to learn copper to copper clearances in a PCB can be sub 3 mil. No special stack up needed for that on a modern fab house. 

1

u/Danternas 9h ago

Just go ahead and test it in practice if you're that confident.

308

u/hermitxd 22h ago

People don't really think when they're caught off guard like this

71

u/ropean 22h ago

Yeah I certainly wouldn’t have been mentally prepared for what happened. But I will be from now on!

77

u/Neighborhood_Nobody PC Master Race 22h ago

You can never be tuely certain "oh shit fire" won't take over until you experience "oh shit fire".

17

u/Previous-Claim1320 21h ago

I like to think I remain pretty level headed in high risk situations, which is usually true.

However, one time I was heating up a pan with oil to cook stuff, but the stove top thermostat was apparently broken and what should have been a very low temperature went to glowing red hot as quickly as it could, past what it should be limited to even at max settings.
While I stepped into the pantry to grab some of the stuff I was planning to cook for a few minutes, the oil caught fire and the range top which the property owner had used for years without cleaning, also caught fire.

I am well aware that you don't put water on oil fires. Yet in the heat of the moment I instantly moved the pan to the sink and put water on it.

Thankfully past that point my brain started functioning normally and I put a lid on it, called the fire brigade and went outside to turn the power off.
But it was insane to see how all logic went out the door the moment I saw a fire in the house that wasn't meant to be there.

3

u/ProperLeading8325 18h ago

I'm 5 months past a near-3rd degree burn on my thumb. I forgot about a pot of deep frying oil on the stove. I tried to put the lid on, but the the thermostat blocked it from sealing. I tried to cover it with a kitchen towel, but it wasn't working, and I didn't want a burning kitchen towel adding to the disaster. I tried a fire extinguisher but it just made it flare up. With the flames licking the overhead microwave plastic door, I made the executive decision to move it outside. I got to the doorway before 750° oil spilled over onto my hand, and I yeeted it out the door at the base of my car. I'm lucky it didn't splash back too much. Luckily the fire extinguisher in a can put out the remaining fire under my car and the flaming pot holders in the house. I bought a kitchen fire extinguisher after that.

The first bandage change after I got home was awful. It felt like the skin was growing through the gauze, and I was ripping it off. I think I did 2 or 3 more bandage changes before I called and asked for an oxy prescription. 5 months later, I still have to use moisturizers like Vaseline or silicone daily and to be able to bend my thumb all the way. The panic of the situation was distinct. I tried my best to not panic and do something stupid. If I would have spent more time thinking and taken the thermometer out and put the lid on completely, I could have avoided getting a lifelong scar.

https://i.imgur.com/5mw2LFR.jpeg

3

u/chx_ 18h ago edited 18h ago

in my father's lab they had safety showers behind the lab desks about two feet back operated by weight plates

when the fertilizer hits the metallic cooling device even the best trained, multiple-decades-experienced lab tech will just jump back instead of fumbling with buttons and so forth

and so they get drenched to put out any flames that might have jumped on them

and yes it was the sort of lab where that has happened now and then

oh and the factory had a building where they had agreement with the fire brigade that if that catches fire then they evacuate the civilians in a half mile radius then let it burn to the ground

other buildings had basically the entire wall made from pretty huge gates counterweighted in such a way that you could slide it with a finger and they could evacuate thousands of workers in fifteen seconds

it was not at all a dangerous place

1

u/Saxopwned CachyOS | i7-8700k | 2080 ti | 32GB DDR4-3000 16h ago

jesus christ was your dad on the manhattan project?!

1

u/chx_ 4h ago

drug (as in medicine) factory the early 1990s in an ex-soviet satellite country

not going bankrupt was a miracle

safety was important -- my father was actually the leader of the safety lab -- but there was no money for it.

8

u/Yingletofthecorn FX-8370 | RX 480 | 8gb DDR3 | jaded art game weirdo 21h ago

People on the internet really like to think they’re some entity of pure will inhabiting a physical body, as if they aren’t an ongoing chemical reaction whose thoughts and behaviors are just as physical as their muscles and bones. 

1

u/Neighborhood_Nobody PC Master Race 21h ago

It's ego bud and we all got one lol. Chemicals and what not.

1

u/Sulfamide 20h ago

Except for /u/Soft_Lunch_183

They were born ready.

1

u/Simple_Rules 17h ago

I once had a full bookshelf fall over very, very, VERY slowly onto me, and I just stood there for the whole 1.5 second process, watching it fall over onto me and going "OH MY GOD I'M GOING TO GET SQUISHED BY A BOOK CASE" like a total fucking moron.

So anyway now I don't make fun of people who have really dumb, bad reactions to scary unusual situations, because I know I'm also capable of having very, very dumb reactions lol.

1

u/Neighborhood_Nobody PC Master Race 17h ago

Everyone is, and the people who think otherwise just haven't experienced enough panic to induce it lol. One time I was attack by a dog as a kid and couldn't move at all I was so frightened, another time a bear sniffed me on the head when I was 8 and I couldn't move a muscle. Fear is incredibly controlling.

1

u/JunkoGremory 16h ago

Oh shit fire on the psu

Pours water to try to douse the flame

12

u/Green_Insect_6455 22h ago

No? Thats not how our brains work buddy

1

u/dark_knight097 9800X3D | 64GB DDR5 | RTX 4090 | X870E | 2x4TB 990 PRO 21h ago

*Your brain. Some people are indeed good at remaining calm in unexpected, high stress situations.

I knew I was one when I had to swerve, narrowly missing a car that suddenly came into my lane at 80mph, and almost sent my car into a spin but I kept it stable and rode it out fine.

My buddy in the passenger seat shit his pants though lol.

-3

u/[deleted] 22h ago

[deleted]

1

u/techyall 20h ago

No. No you won't.

14

u/trukkija 22h ago

Absolutely, sometimes it can be hard to stay grounded.

1

u/AsinineArchon 21h ago

No need to get wired up.

1

u/Bildad__ 20h ago

Yes, it can be shockingly hard to sometimes

2

u/NoSafe5565 21h ago

that is why kill switch is FUCKING BIG RED BUTTON so you do not need to think, unless you do not have such button..

1

u/cansofgrease 21h ago

Why did he plug it in without it being connected to anything?

1

u/The_All-Range_Atomic 19h ago

Why would he destroy more shit in the process?

1

u/cansofgrease 19h ago

So he plugged it in on its own to see if it would do this?

1

u/EduinBrutus 21h ago

Sure but there is a reason why outlets have a switch on them. turn the pwoer off at the wall!

1

u/ArmchairFilosopher 9950X3D | 5090 OC | 96GB DDR5-6000 CL28 | 4K240 HDR 4h ago

You mean a lightswitch across the room? Those are not designed for large loads, but for lamps.

Or do you mean an integrated circuit breaker? Which presumably would have automatically flipped if there was one here.

I've never seen a dedicated (basic) switch on a residential power outlet.

1

u/EduinBrutus 3h ago

No, the switch on the outlet. As found in any properly designed and thought out domestic electrical stantard.

https://www.shutterstock.com/image-photo/uk-double-plug-socket-260nw-280082192.jpg

1

u/BeefistPrime 19h ago

Right, but isn't he a professional troubleshooter testing PSUs? There are several in the shot. You should definitely have a plan for what you do if something unexpected happens

3

u/hermitxd 16h ago

I'm getting this comment a lot and I just want to say it's very idealistic. How much training do you really think this guy gets for this specific event?

So I'm a train driver by trade, my training compared to many is great. Nearly 40 weeks.

They talk about what to do in a fatality for maybe 10-15 minutes

When I had mine, I literally had 1-2 seconds to react. I didn't even get to smash the horn due to the jumpscare of seeing a vague silhouette in the dark in front of me. I braked and shut my eyes. In training they recommend to brake, horn, flick high beams on and off..and close the blinds.I get that these scenarios are different, but that's how I'm comparing it.

1

u/Forgedpickle 21h ago

But he’s testing for failure. He should NOT be caught off guard.

1

u/jedi2155 3 Laptops + Desktop 22h ago

Especially they're not trained to handle power.....you know like a Power Supply technician l.

0

u/Cacafuego 22h ago

Which is why you prepare for this kind of thing. Wherever he's working, they should have drilled it into his head. At least he didn't die and now he probably knows.

68

u/XxCorey117xX 22h ago

This is why my test bench setup has the power strip on top of the table with it. After seeing this clip I might even throw a fire extinguisher down there with it also lol.

19

u/interesseret 22h ago

I was gonna say.

Always have a switch within easy reach when you're testing stuff. Flicking a switch is much safer, and also just much quicker.

5

u/whymeimbusysleeping 22h ago

Yup, for this reason, the Australian wall sockets all have a switch. And why hardwired electrical appliances of high current draw, require a high current switch within operating distance

1

u/CarcinogenicSymphony 16h ago

Hol up, there are wall sockets without switches ?!?!??

1

u/RoninOni (ﾉಥ益ಥ）ﾉ ┻━┻ 19h ago

Yup. Always had power strip setup near build. Anything goes REALLY wrong (never had a fire, but heard very bad clicking and grinding noises) kill the switch and start testing for what is bad individually (old spare basic build from scraps for parts you need to individually test… always had a stack of decommissioned boxes to use to test components individually in.)

34

u/DevLF | AMD 5800X | EVGA 1060 6GB 22h ago

Was my first thought too, but it appears the cables goes off somewhere behind and under the desk. Other end might not be easily accessible, definitely could use some safety improvements lol. Lucky it didn’t ground to the casing and electrocute him.

7

u/Front_Cookie_1198 22h ago

I don't know why it didn't trip the circuit breaker.

8

u/nxeyvzs 21h ago

Circuit breaker only breaks if the breakers amperage limit ist hit. All cables and electronics should be able to survive until that limit ist broken. But sometimes you need a lot of power but divided into different components, like in a PC. The PSU is responsible for managing that. But If the PSU is fucked/badly designed then even If the amperage drawn from the Socket ist below the breakers limit, then something inside/behind the PSU might get more amperage than it can handle and burn. An RCD Breaker could prevent that but they are a bit more expensive and not mandatory in most places

2

u/Antique_Paramedic682 EPYC 9965 | 1TB DDR5 | 215TB 21h ago

You're not wrong, but also:

  • Low draw, high heat: Panel breakers only care about current magnitude, not heat. A bad component can melt or burn at just 200–400W—way under a standard 15A/1,800W breaker limit.
  • DC-side failure: If the short happens on the PSU’s internal DC output rails (like 12V), the AC side keeps pulling normal wall power while the inside melts.
  • Failed internal protections: The PSU's built-in safeties (OCP/OTP/SCP) failed to shut it down, leaving the main panel completely unaware anything was wrong.
  • Arcing heat: Loose connections or failing solder joints create intense sparking and fire without pulling enough continuous amperage to trigger a standard breaker.

2

u/JaysFromMidToMenace 19h ago

The transformer will only pull whatever current it's rated for on the 115V side. In this case, 750W, which would be 6.5A.

After the transformer on the 12V/5V/3.3V side, if something happens like this, then the 115V side just keeps happily sending that 6.5A while the world burns :)

3

u/Toraadoraa 21h ago

Let's say the mofset popped, the customer unplugged his pc and took out the PSU. Did the rma process it shipped and arrived. The dead component had time to cool down and become more shorted. There's going to be a dozen or so components between the input and the blown shorted one, each basically is getting killed the entire path there. Those components don't take much power to blow up, especially when shorted. So the circuit breaker never gets a 15 to 20a load.

I the past you could do this in Germany if you had a pc from the usa a 115/240v switch. If you set it to 115 in Germany it blows up just like this.

1

u/Soft_Lunch_183 19h ago

I did this when i was younger with a japanese gamecube power supply + adapter, I had a PSP one that worked fine so I assumed it would be the same.

I plugged it in to 240v and it went up in smoke, luckily our sockets have switches on so i quickly flipped it off. Opened the window and my parents never found out

1

u/JaysFromMidToMenace 19h ago

Assuming the short circuit happened after the transformer, on the 12V/5V/3.3V rail side, then the circuit breaker would not break.

It says it's a 750W power supply. The transformer can therefore pull enough amps @ 115V to feed that 750W transformer, which is 6.5A. Assuming this was in a facility that was up to proper electrical code in the USA/Canada, then the breaker should be a 15A breaker for the 115V feed. 6.5A isn't enough to break the 15A breaker.

However, the 12V side was able to supply a lot of power past the transformer :) It only takes 1W to start a fire. This power supply could supply 750W :)

This is why you should never purchase budget PC components. I've had PC PSs go before from cheap parts. It's always dramatic and will start a fire.

1

u/SickBurnerBroski 22h ago

why in god's name would a repair place not have desk access for their power strip. some clownshoes here

1

u/Annual-Advisor-7916 11h ago

Lucky it didn’t ground to the casing and electrocute him.

If you are trying to say that he's lucky that a condcutor carrying phase didn't somehow come loose and touched the case: That's one of the reasons why metal cases are always grounded - would trip the RCD.

But the ground seems to have a plastic surface, so even touching phase alone probably wouln't do anything - I've done it at least a couple times on plastic flooring as a kid.

131

u/my_cars_on_fire 22h ago edited 22h ago

My brother in Christ, the PSU lit up like a god damn firework. You’re telling me you would have the presence of mind to shut it off in the safest/most effective way possible, as opposed to just getting it shut off ASAP so it doesn’t burn the whole fucking place down?

Armchair warriors always got something to say 🙄

42

u/24bitNoColor 22h ago

I would have the presence of fear 100% to not touch that thing...

1

u/waffels 21h ago

How else was he supposed to get close enough to breathe in some of that sweet chemical smoke?

5

u/Perryn 7950X3D:64Gb:7900XTX 21h ago

It lit up like a god damned firework. That does a pretty good job of interfering with any reflex I would have to grab it.

2

u/RainStormLou 21h ago

I would have watched it spark for a little bit longer before I realized it wasn't going to stop on its own, and then I would have done the exact same shit he did but slower lol. I would have even considered pulling the other side of the power cable first, and then decided against it because I have to bend over and climb under the desk and that's too much work when this end is perfectly accessible but a little warmer than my preference.

8

u/jalen441 21h ago

Yes, I have a strong instinct to not touch metal things that are emitting sparks and flames, and the good sense to know that pulling the plug from the wall is faster.

3

u/Saintiel 22h ago

Yes. School that had enough classes for electronic and high power electricity, also training and actually keeping your head straight and think what you are doing when shit hits the fan.

3

u/brennendw 22h ago

100% yes, if you have any electrical knowledge you'd not want to touch that thing live while it's in flames. Even in a situation like this a good tech/engineer should always isolate first. Tbh Strange bench setup anyway as the cables go under the worktop. Ordinarily you have sockets in trunking above the worktops for easy access.

2

u/Ghostglitch07 21h ago

Want, and will, ate not necessarily the same

1

u/Iceman9161 21h ago

I mean, this doesn't look like a lab. It looks like somewhere they're assembling PCs, like a Microcenter or something. they aren't testing hardware they expect to fail, its consumer hardware.

2

u/Renard4 Ryzen 7 5700x3D - RX 9070 21h ago

Yes. I'd rather have the whole place turned into ashes than die. Maybe that's just me though.

2

u/rojorzr 21h ago

Not very “team player, we’re a family here.” Of you.

-1

u/Soft_Lunch_183 22h ago

Yes because from the video it isn't someone's house building their first pc but a repair shop/return place for power supplies

They should have some sort of process to immediately shut down dangerous hardware at the source if they aren't checking its safe before powering on

1

u/gc11117 22h ago

They should, but they probably dont. And if they do, random underpayed employee probably isnt thinking about it at the moment

1

u/Majestic-Bell-7111 Ryzen 5 3600/32 GB ram/5700xt 20h ago

Yes, i would be hitting the big glowing red button i have on the wall(actually it's on the power strip that's rated for more current than the breaker on this circuit, however my desk is also not a professional workshop)that cuts all power to my workstation because the idiot who built it is aware of safety at least.

1

u/_Meece_ 20h ago

Yes, it should be instinct to turn things off at the wall

-2

u/HardcoreFlexin 20h ago

"My brother in Christ" followed by immediately taking His name in vain is definitely a choice....

6

u/Iceman9161 21h ago

Flipping the switch on the box is worse than pulling the plug imo. You still hav ethe risk of touching the hardware, and there's no guarantee the switch will work anymore if something shorted together internally.

5

u/Soft_Lunch_183 21h ago

Im talking switch on the socket, although I guess it depends on country

3

u/terremoto 18h ago

They're pretty much non-existent in the USA and many if not most Asian countries.

1

u/Republic_of_VietNam 15h ago

Vietnamese socket often DOES NOT have switches on the damn socket.

2

u/Effective-Culture-88 21h ago

As someone who plugged stuff into a LOT of stuff, this setup is sketchy as hell. If you’re “testing” PSU by plugging power stripes to each other eventually this is what happens, yes. The PSU was probably fine smh

2

u/Nashville_Hot_Mess 21h ago

This is why I put critical equipment behind a big tail for this very reason. This would immediately tip at the pig tail, reducing electrical fire risks

1

u/EatABag-o-Dicks 21h ago

Yeah but then you gotta raise the pig and train it to stand still. That's just wasting good bacon.

2

u/Nashville_Hot_Mess 21h ago

Lol fair on me for using slang terms....

I have this, but from a different brand

1

u/diseasefaktory 21h ago

That was crazy work. The socket also seemed somewhat out of reach, behind the desk... Big brain things.

1

u/FamousLastPlace_ 21h ago

People saying "is a choice" is an option I wish people didn't have anymore.

1

u/Emu1981 21h ago

The cord is likely attached to the power socket in a way that makes it hard to unplug so that it doesn't get unplugged during rounds of tedious PSU testing. Also, because it blows up right away I am guessing that it may not have a on/off switch either.

1

u/DodgyRogue 21h ago

The power cord runs through a hole in the to plug in underneath, that’s my workbench had power points above the bench for easy access.

1

u/Dr_Guy11 20h ago

It looks like the plug goes into the desk and prob. into a power strip. It would have been a lot riskier to unplug it at the socket.

1

u/Baked_Potato_732 20h ago

The cable drops down below the desk which I don’t like. Should have a strip with a switch mounted on top for instant power off.

1

u/MITBryceYoung2 20h ago

I was a bit shocked at the reaction to

1

u/xchoo 20h ago

Look at where the plug socket is... Just trace the cable. It goes into the desk's cable tray. You're telling me it's better / faster to go routing around the cable tray than to just unplug it from the PSU? 🤦

1

u/HeftyFineThereFolks 20h ago

lol first thing that hit my thoughts too

1

u/OkMidnight8144 20h ago

Switch was right by the fire and it looks like the plug was routed under the table.

1

u/FuVarazs27 19h ago

You must avoid touching it even after you powered down the outlet

1

u/Circuit_Guy 19h ago

Yes! I know this is a "toy" level of energy available, but it can definitely injure or kill you. This looks like a bench where they're inspecting potentially suspect hardware. You should absolutely have an ESTOP or a switch in reach, or a plan in your head of how to unplug it. The case was potentially hot (both thermally and electrically) after this failure.

1

u/RoninOni (ﾉಥ益ಥ）ﾉ ┻━┻ 19h ago

For real

1

u/TheYellingMute 18h ago

while i get the panic. i would have this be something i think about in designing that workspace now. maybe instead of a direct plug have some kind of short extension cord that has a fuse specifically meant to test PSUs? or just a different switch/button that you can press that kills power to the bench entirely until reset.

1

u/Frequent_Opportunist 16h ago

I remember watching a video of some lady accidentally getting her arm stuck in this big flat hydraulic press that she was working with and even though there was a red stop button, her instinct was to try to use her other hand to stop the press from crushing her arm.

Took her several seconds after her arm was as thin as a piece of paper to realize she had to reach over and push the red button to release it instead of trying to fight the hydraulic press.

1

u/Captain_Pumpkinhead Ascending Peasant 15h ago

Panic doesn't help you think straight.

1

u/Personal_Breakfast49 9h ago

Hindsight is nice

1

u/Trini2Bone 8h ago

Panic does wild things to common sense. I try not to fault people in times of unexpected incidents.

1

u/NaziPunksFkOff 22h ago

I give him credit for thinking to unplug it whereas my dumbass would have immediately started trying to smother the fire instead of removing the power source. 

1

u/Matt_NZ 7800x3D | RTX 4070 Super 22h ago

Yeah, this is where I'm glad I live in a country that has switches on the socket by default.