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Fixing a loud PSU fan without dying

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Re: Fixing a loud PSU fan without dying

#31

Post by jijijijij »

magicalhippo wrote: post #29
serf wrote: post #19

Earlier quoted context omitted.

doing this on a fan that used a dry lubricant can burn a wire lead from increased startup torque requirements to get it spinning. it's not bad advice but it's worth noting that petroleum jelly is pretty thick compared to a machinists' oil or dry graphite.

Then there are the fans with magnetic bearings. Had a few that started making noise but never figured out from where, given there are no touching parts.

I think magnetic bearings necessarily also got touching parts.

Re: Fixing a loud PSU fan without dying

#32

Post by 6510 »

stavros wrote: post #20
userbinator wrote: post #16

I've "fixed" countless noisy computer fans over the years with simple lubrication. Peel off the label, remove the bung, pry out the circlip and pull the rotor + blade assembly out, clean off any remaining old grease/oil, and then pack the bushing with petroleum jelly before reinserting the shaft. Reassembly is the reverse of disassembly.

I have a personal rule that I only follow instructions when I understand more than 10% of the words in them, so I'm buying a new fan.

I would glue an additional fan onto the psu hoping it would stay cool enough for the master not to notice the heat build up. If that doesn't work open it up and cut the wires or unplug the fan.

Re: Fixing a loud PSU fan without dying

#33

Post by m463 »

I learned about fans many yea^H^H^H decades ago when I had a sun external scsi disk box.

One day at Fry's Electronics I found they sold external scsi cases. So I bought a case and a cheaper bare scsi drive and hooked it to my sun.

The fan was quieter too!

and after a few months, the fan started getting louder. and louder. and then one day when the drive seemed to stop responding, I found it had failed.

sun fans were annoyingly loud, but they had one interesting property: THEY ALWAYS SPUN.

Re: Fixing a loud PSU fan without dying

#34

Post by analog31 »

userbinator wrote: post #25
duskwuff wrote: post #23

Earlier quoted context omitted.

Modern computer power supplies are far less dangerous than CRTs were. CRTs were dangerous because they used extremely high voltages (often as high as 25 kV), and that voltage was often present on the CRT itself, which acted as a capacitor. The capacitance of the CRT was relatively low, but it still stored enough energy to be very hazardous. There's ways to safely discharge them, but you absolutely need to know what y…

The main danger with CRT HV is not the HV itself but what the shock will make you do, such as jump and cut your hand on something sharp in the chassis, or even crack the neck of the tube, or fall and hit yourself. There is very little current available, especially if the set has been off, but it's comparable to a very painful static shock. Instead, the "low" voltage B+ supply is far more dangerous when the set is on,…

Beware. I took a poke from the focus anode of a CRT when I had a job repairing mainframe terminals in the early 80s. I thought I had discharged it, but apparently I didn't.

I had to sit down in a quiet room for the rest of the work day, before I could function again. It was probably 13 kV, which was typical for monochrome displays back in the day.

Also, anything in a CRT television can kill you because TV's tended to have a "hot" chassis. The repairmen always plugged a TV into an isolation transformer so they could ground its chassis while working on it. There's a lot of counterintuitive things about those old electronics due to clever cost reductions.

Re: Fixing a loud PSU fan without dying

#35

Post by magicalhippo »

GuB-42 wrote: post #28
sonofhans wrote: post #3

An important side note is that Cooler Master’s “10-year Warranty” is garbage: > I looked at Cooler Master’s warranty, and for issues within the first two years you have to deal with the retailer. That would be Amazon in my case. So I looked at Amazon’s information on warranty issues. Their policy is that if it’s more than 30 days since purchase, you have to send it off to a third-party repair center and wait for them…

In Europe, it actually matches the law, it is actually better. - You have a 14 days retraction period, where you can send back the item and get your money back, defect or not. Amazon gives you 30 days and free return shipping. - Legal warranty is 2 years and is provided by the seller, not the manufacturer. It is Amazon in this case, but it could be a brick and mortar shop or any other seller, including independent se…

Similar in Norway, though not it's only for production defects and not expected wear and tear from regular use, or misuse etc.

However it's on the seller to prove it was not a production defect if they don't want to fix or refund.

Back when CD burners kept getting faster and faster my buddy bought a 4x writer and ended up with a 52x writer as they kept breaking down after 12-18 months. IIRC he went through four or five before getting the 52x which lasted.

Re: Fixing a loud PSU fan without dying

#37

Post by rpcope1 »

GuB-42 wrote: post #30
userbinator wrote: post #16

I've "fixed" countless noisy computer fans over the years with simple lubrication. Peel off the label, remove the bung, pry out the circlip and pull the rotor + blade assembly out, clean off any remaining old grease/oil, and then pack the bushing with petroleum jelly before reinserting the shaft. Reassembly is the reverse of disassembly.

Never had much success doing this. At best, it worked for a few days, maybe weeks before buzzing again. I tried a variety of lubricants, stuff that I had on hand (WD-40, 3-in-1, lithium grease...) but not petroleum jelly though. So unless it is a weird fan I can't find elsewhere, now, I just buy a new one.

WD-40 isn't a lubricant, 3 in 1 is really a cutting oil and too thin, and I can't imagine lithium grease doing well in a high speed bearing...it's really only good because I think it's less toxic. These are all real thin and not appropriate in a bearing. I'm not sure about petroleum jelly, but as crazy as it sounds I've packed all sorts of bearings including fan bearings with basic synthetic marine grease (the pink shit that comes in tubs and grease cartridges), or occasionally heavy weight synthetic gear oil (think 75w90), and profoundly improved the life of things and reduced drag. Only real drawback is god forbid you get real grease on your clothes or something you care about cause it's not coming out.

Also if it came packed with graphite or something else exotic none of the above applies and doing the above can burn a motor out.

Re: Fixing a loud PSU fan without dying

#38

Post by ycombinatrix »

hobs wrote: post #6
mkayokay wrote: post #2

A new semi-passive 850-watt fully modular PSU is around EUR 130, the Noctua fan around EUR 30. I guess if you know electronics and how to safely handle the PSU internals, the risk of injury is low, but I personally would not risk it for EUR 100. Also, if the only problem was the noisy fan, I guess selling it used would have returned most of the investment, leaving him with like EUR 50 in added cost. Compared to the p…

Hilarious to read this on "hacker news" - replacing a standard fan is too dangerous! This is not styropyro.

PSU capacitors can kill you, even after being disconnected from mains power.

Re: Fixing a loud PSU fan without dying

#39

Post by rpcope1 »

shmerl wrote: post #36

Get PSU from original manufacturers instead, someone like Seasonic. Most common brands simply repackage stuff and not really the best quality.

Seasonic makes (made?) really excellent PSUs, but they've been real thin on new inventory over the last year or so. Maybe they're getting out of direct retail? Even a second hand older Seasonic platinum PSU is still hands down better than a lot of the new garbage that's getting turned out.

Re: Fixing a loud PSU fan without dying

#40

Post by victorhooi »

hobs wrote: post #6
mkayokay wrote: post #2

A new semi-passive 850-watt fully modular PSU is around EUR 130, the Noctua fan around EUR 30. I guess if you know electronics and how to safely handle the PSU internals, the risk of injury is low, but I personally would not risk it for EUR 100. Also, if the only problem was the noisy fan, I guess selling it used would have returned most of the investment, leaving him with like EUR 50 in added cost. Compared to the p…

Hilarious to read this on "hacker news" - replacing a standard fan is too dangerous! This is not styropyro.

I think perhaps you might have not read the entire article? =)

The danger isn't so much in the fan, but in that the fan is INSIDE OF A COMPUTER PSU. There are mains AC voltages (220V, or 110V) here, and even if unplugged (which is should be) there are also capacitors in there, which you should definitely be cautious of.

I've worked in DC (datacenters) before - and I've seen people accidentally drop screws into power supplies...and well, electrical arc, boom, you can guess the rest. And in a domestic situation, a 4" cooling fan (yes, I know, larger) stopped suddenly due to a motor issue, and send flying bits of plastic shrapnel around (always wear eye protection!).

This isn't quite like tinkering with your little Arduino board, or Raspberry Pi.

If you did read the article =(.... I think that's a bit arrogant and disingenuous to make fun of people saying you should be cautious around things that are connected to AC mains, or that involve capacitors.

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