[SOLVED] How to choose new fan for PSU?

crowler366

Prominent
Dec 18, 2019
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510
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Hello, I bought Corsair CV550 not so long ago and recently I put my PC case on the table instead of under the table so I am hearing fans louder now. After some testing, I realized my PSU fan is making loudest noise, so I would like to replace it, I know it can be dangerous but I have done it before and took all precautions when it comes to opening PSU. Can someone help me find quiet fan to replace the corsair one? I can't even find corsair's fan name anywhere. Thank you in advance
 
One more question if someone can answer. How do I recognize the quality of PSU? CV550 and RM550x are both 550W but RM is much better like you said. How do I know which one is better if they are the same wattage
Easier than trying to find a review of each psu you might find is to refer to a reliable tier list. They rank the more 'popular' psu into tiers of quality. Find a common or popular brand on a high tier and go search for that model on Amazon or another shopping site.

Toms has one as well as Linus Tech Tips which is particularly complete (meaning a lot of PSU brand/models) and is fairly frequently updated. I think the LTT one can be accessed a spread sheet and has all the technical features listed, if that's of interest to know. You can find out the protections, the regulation type, hold-up, fan types and other minutiae.
 
Reactions: crowler366
Hello, I bought Corsair CV550 not so long ago and recently I put my PC case on the table instead of under the table so I am hearing fans louder now. After some testing, I realized my PSU fan is making loudest noise, so I would like to replace it, I know it can be dangerous but I have done it before and took all precautions when it comes to opening PSU. Can someone help me find quiet fan to replace the corsair one? I can't even find corsair's fan name anywhere. Thank you in advance
It's not really as dangerous as people make it out to be but if you're paranoid about it just bleed off the big caps by shorting across their leads with a screwdriver and you'll be safe. They're not made to store a whole lot of energy so about all you'd get is a little spark and it's done.

If your PSU isn't a high efficiency unit that only turns the fan on under heavy load then you need a super quiet fan. I'd say just get a Noctua of same size and put it in there. But you may not find one as some PSU's use strange sizes...like 138mm instead of 140mm...to fit in the case. You also might have to get a 15mm, or extra thin, fan if they used one of those. It might operate at max RPM all the time so figure on getting one around 1200RPM max, or maybe 800RPM if you don't mind roasting the PSU a bit.
 

crowler366

Prominent
Dec 18, 2019
20
0
510
0
It's not really as dangerous as people make it out to be but if you're paranoid about it just bleed off the big caps by shorting across their leads with a screwdriver and you'll be safe. They're not made to store a whole lot of energy so about all you'd get is a little spark and it's done.

If your PSU isn't a high efficiency unit that only turns the fan on under heavy load then you need a super quiet fan. I'd say just get a Noctua of same size and put it in there. But you may not find one as some PSU's use strange sizes...like 138mm instead of 140mm...to fit in the case. You also might have to get a 15mm, or extra thin, fan if they used one of those. It might operate at max RPM all the time so figure on getting one around 1200RPM max, or maybe 800RPM if you don't mind roasting the PSU a bit.
I can't find anywhere which type of fan it should be? I think I saw there is like airflow type or pressure type of fan or whatever, the corsair one is 120mm so that's not a problem
 

NightHawkRMX

Polypheme
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It's not a particularly good choice for this GPU. It's a waste of money to replace the fan on an entry-level PSU to run a spiky card.
A CV550 will work with an RX570 just fine, but I do agree it is a waste of money to upgrade the fan in such a power supply. It would have been wise just to get a better quieter PSU to begin with.

I can't even find corsair's fan name anywhere.
Its a yate loon fan, a fairly common supplier for power supply fans.

...you may not find one as some PSU's use strange sizes...like 138mm instead of 140mm...to fit in the case. You also might have to get a 15mm, or extra thin, fan if they used one of those. It might operate at max RPM all the time so figure on getting one around 1200RPM max, or maybe 800RPM if you don't mind roasting the PSU a bit.
Not the case here. The fan in the CV550 is 120mm fan, so standard fan size.

or maybe 800RPM if you don't mind roasting the PSU a bit.
That's the main reason I suggest not doing this. The manufacturer specifically picks a fan that can provide the level of cooling needed for the power supply. Although, the CV550 has over temperature protection and you likely wont have any overheating issues if you select a good fan. I still wouldn't reccomend this over just getting a quieter PSU to begin with, tho

Plus its not just plug and play. There is some soldering required to make a standard case/cooler fan work in a power supply.
 
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crowler366

Prominent
Dec 18, 2019
20
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510
0
Thank you all, it was helpful, I will try to sell CV550 and get a better one, if someone can recommend me a good, not so expensive PSU I would appreciate it
 
Thank you all, it was helpful, I will try to sell CV550 and get a better one, if someone can recommend me a good, not so expensive PSU I would appreciate it
I got a great Corsair RM550x off Amazon just a few weeks ago, works perfectly with a Ryzen 1700/RX480 combo, for around $90US. The fan only comes on when I am running folding at home, not gaming and not even encoding videos.

You have to keep checking on the Amazon site over several days to get a better price. And when you get a lower price to finally come up you have to get it then because it may not be that good again for a while.

But the general problem is the same: everything in short supply right now so it's very much hit or miss.
 

NightHawkRMX

Polypheme
Ambassador
You don't even need to spend that much to get something quiet.

An EVGA GQ650w is $69.99 us on Amazon. While definitely not as good of a unit as the RMx, it is still a considerable upgrade from the CV550 and, most importantly, has a semi passive fan mode just like the RMx. So the fan is unlikely to spin much at all with the OP's system.
 

crowler366

Prominent
Dec 18, 2019
20
0
510
0
One more question if someone can answer. How do I recognize the quality of PSU? CV550 and RM550x are both 550W but RM is much better like you said. How do I know which one is better if they are the same wattage
 

NightHawkRMX

Polypheme
Ambassador
You have to look at professional reviews of each unit.

In general, a higher end PSU of same wattage would have a lot of benefits versus a lower end one.

Better performance (tighter voltage regulation, lower ripple, higher efficiency, etc)

Better fan (more reliable fan bearing type, overall noise reduction)

Better design: (More modern platform, more modern design) Sometimes power supplies with older designs such as the CV550 can have problems supporting modern higher end graphics cards, as the design cannot tolerate the load spikes these cards have.

Higher build and component quality (Japanese capacitors, superior mosfets, better soldering quality, better fan) These benefits specifically are very important for longevity of the PSU.
 
Jun 5, 2021
14
3
15
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I don't need to, I only play 1-2 games and have RX 570 which is enough for my needs.
It's less that it's impossible to swap out a PSU fan (because it can be done) and more that unless you're qualified, it's extremely dangerous to do so. There are capacitors in PSUs that store enough charge to kill you several times over, even when unplugged. That's why there are warning labels all over the manual.

Also, the CV550 really isn't a good unit to begin with. The most glaring flaw is that it's group regulated, which really isn't something you should be getting on a remotely midrange system in this day and age.
 
One more question if someone can answer. How do I recognize the quality of PSU? CV550 and RM550x are both 550W but RM is much better like you said. How do I know which one is better if they are the same wattage
Easier than trying to find a review of each psu you might find is to refer to a reliable tier list. They rank the more 'popular' psu into tiers of quality. Find a common or popular brand on a high tier and go search for that model on Amazon or another shopping site.

Toms has one as well as Linus Tech Tips which is particularly complete (meaning a lot of PSU brand/models) and is fairly frequently updated. I think the LTT one can be accessed a spread sheet and has all the technical features listed, if that's of interest to know. You can find out the protections, the regulation type, hold-up, fan types and other minutiae.
 
Reactions: crowler366

InvalidError

Titan
Moderator
It's not really as dangerous as people make it out to be but if you're paranoid about it just bleed off the big caps by shorting across their leads with a screwdriver and you'll be safe. They're not made to store a whole lot of energy so about all you'd get is a little spark and it's done.
First, capacitors are usually mounted flush against the board and have no exposed leads to short out while the PCB is still inside its housing and by the time you have pulled it out from there, you will have shocked yourself a dozen times by touching live surfaces if they haven't shorted to something else first.
Second, any remotely decent PSU will have bleeder resistors or a "smart" bleeder circuit that will drain capacitors faster than you can open the PSU, so there shouldn't be any sparks unless you are attempting a world record for pulling a PSU out of a system.
Third, even if the bleeder resistors are missing, the 5VSB circuit should get you most of the way there anyway.
Fourth, if all of the above failed, 470-820uF worth of input caps charged to 300-400V is going to cause a bang loud enough to make you wish you had ear protection - I have shorted photo-flash caps charged to 300+V a couple of times.

The danger is relatively low, largely because there are multiple layers of intentional and incidental safety built into PSUs.

As others have mentioned though, the best reason not to bother upgrading the fan in CV-series PSUs is that they shouldn't have bought such a low-end model to begin with.
 
...., you will have shocked yourself a dozen times by touching live surfaces if they haven't shorted to something else first.
....
That is pure fantasy-horror, fear mongering, meant to scare people. I've worked on dozens of PSU's and never shocked myself once...if you have let us know with specifics. Fixing a PSU in a way that works reliably in your system may require some pretty good tech skills, but just poking around inside a PSU safely isn't high skilled tech work. You can do so with simple precautions...and most of the most important ones were taken already for you by the designers.

I've discharged 10,000mF caps in the HV power supply of UHF transmitters (800VDC plate voltage) and all I ever got was a pop...never anything as horrendous as you relate. There's just not much energy stored in a capacitor, even big ones. While there are electrocution hazards in such equipment, that isn't the hazard from accidental discharging a capacitor... it was jerking your hand/arm out of the equipment and cutting yourself.

If the cap's not got an exposed lead, e.g., it's mounted flush to a PWB, then all the better as it's protected against accidental touching. Just short everything you can get to to ground if you're concerned.

OP said he's aware of the hazards. That means to me he's not likely going to go fondling things inside with his fingers anyways.

But here's another reason this fear-mongering is more imaginary than real: IF there are sufficiently hazardous voltages inside the PSU after removal from primary mains, then there HAS to be the safety bleed-off resistor or circuit included in the design you refer to. It's standard design practice in modern electronics and probably a requirement for UL and other certifications. I'd be very surprised if it's not present in even the cheapest PSU on the market (it's cheap to do), but on the outside chance that's why short everything to ground (the case) that you can.

Also, a curious observation, I don't recall that any of my PSU have been labeled with required cautions about hazardous voltages being present when removed from power. How can they get away with that and still carry UL and other certifications?

The WORST hazard I'd admit to as a serious consideration is that while poking around someone's going to unwittingly break the PSU and leave it in a state it could damage/destroy the system, or worse create a fire hazard.
 
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Jun 5, 2021
14
3
15
0
Can you recommend me better PSU that is not overly expensive? Even CV550 is almost 100$ where I live
Not sure what country you're in, but check the availability of a Cooler Master MWE Bronze V2. These are fairly common to find in Europe where Corsair has less of a presence than they do in North America.
 

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