Question Replace fan, or entire CPU cooler?

[Fardringle]

I've had a Scythe Fuma 2 cooler attached to my Ryzen 9 3900X for just about three years. It seems to do a good job keeping the CPU temperatures under control while the CPU runs at 100% utilization for BOINC distributed computing projects.

However, I've noticed recently that the front fan on the cooler is becoming quite noisy, and produces a loud buzzing/grinding sound when it spins up beyond about 50% speed. The fan does not appear to have an axle hole to add oil to the axle or bearings, unfortunately.

So, I'm looking for input on whether I should shop around for a decent 120mm x 15mm fan and just replace that front fan, or if a good fan would cost enough to make it worthwhile to replace the entire cooler. Possibly an AIO system?

I do hope to eventually replace the 3900X with either a 5950X or a 7950X CPU (and a new motherboard), if that makes a difference.

 

[BoomerD]

You MIGHT be able to lubricate that fan...Many fans have a sticker on the front or back. Peel that back and there should be a hole in the fan that will allow you to lubricate the fan with a drop or two of light oil.

 

[Tech Junky]

I always swap out the OEM fans for Arctic P PWM PST fans. They're quiet and durable and save headers since you can chain them together. 5 packs of them are only $40 on Amazon. If you happen to need a replacement it just takes an email and you have another one within a week. I used to use a fuma as well with dual Arctic fans no problem.

 

[Fardringle]

I'm honestly not a fan of the Arctic Pxx PWM PST fans. Chaining the power headers is nice, and they are quiet while they work. However, I bought a pack of five 140mm fans for my PC case in 2021 and three of them died completely within the first two months. And it would have cost almost as much to ship the dead fans back to get them replaced as it would have to just buy new fans so I didn't bother.

Maybe I just had an unusually bad experience, but I won't buy any more of them.

 

[Tech Junky]

I would say its a bit off as I've bought a few 5 packs now and didn't have to ship the one I had replaced back to them. The first build I used them on was back in 2020 and my current setup is using them as well for a year and a half now. The one I had replaced was self inflicted as I was moving it while powered on to change the flow direction and nicked one of the blades on something and ended up with a hairline fracture around the hub that caused a wobble and noise.

 

[Fardringle]

You MIGHT be able to lubricate that fan...Many fans have a sticker on the front or back. Peel that back and there should be a hole in the fan that will allow you to lubricate the fan with a drop or two of light oil.

I checked. There aren't any holes under the stickers. But thank you for the suggestion.

 

[BoomerD]

I checked. There aren't any holes under the stickers. But thank you for the suggestion.

OK, looks like those are sealed. I should have checked before I made the suggestion. In that case, you can just replace the fans with a quality 120mm fan that's made for pressure, or replace the entire cooler/fan assembly. Myself, I'd opt for new fans...and give the radiator a good "blow job," I don't know for certain your cooler will handle the 7950X or not...MAYBE...

 

[Paperdoc]

Just a couple comments.

MOST fans now (for 15 - 20 years) are built so that you can NOT reach the bearings and add oil. To disassemble enough to reach bearings would normally break the plastic moulded frame parts so you cannot re-assemble. So your only option is replacement. Besides, the reason for noisy worn bearings is usually NOT lack of oil - it is that the bearing sleeves themselves have worn to larger bore diameter, and no amount of extra oil will fix that.

I agree - replacing the fan is better than replacing the entire unit. Normally I would encourage you to look particularly for a fan with "high pressure" specs since this is blowing air through a finned heatsink. BUT I note that the specs for that cooler system says the Kaze Flex fans used have relatively mow pressure ratings. The 15 mm thickness one it is rated as 32 CFM air flow and 0.62 mm water max backpressure, both of which are low. So lots of fans would do that or better.

Consider replacing with a more common 25 mm thick unit. That WILL fit onto the cooler unit since the thin fan is on the OUTside of this unit. It may take a little effort to get the spring clips that hold the fan onto the heatsink to fit the thicker fan. The real limit may be how much clear space there is near the cooler to allow a thicker fan, ESPECIALLY over the nearby RAM modules. In that line of thinking, one option would be a second unit of the 25 mm Scythe Kaze Flex II fan that is the other part of your system. Its specs are 53 CFM air flow and 0.97 mm water max backpressure. The Scythe web page promotes a feature that the thin fan rotates in the opposite direction from the thick one for better performance, but I doubt that is a huge factor, and would be out-done by simply using a higher-rated replacement.

A significant factor in heat removal capacity is dust accumulation between the fins of the heatsink. So when you take things apart for this, I suggest you ASLO remove the thicker fan in the middle and do your best to poke and blow out any dust you can before re-installing the fans.

 

[Fardringle]

I agree - replacing the fan is better than replacing the entire unit. Normally I would encourage you to look particularly for a fan with "high pressure" specs since this is blowing air through a finned heatsink. BUT I note that the specs for that cooler system says the Kaze Flex fans used have relatively mow pressure ratings. The 15 mm thickness one it is rated as 32 CFM air flow and 0.62 mm water max backpressure, both of which are low. So lots of fans would do that or better.

I hadn't looked at the fan specs, so I appreciate that info. Not having to worry about really high CFM makes things a little easier.

Consider replacing with a more common 25 mm thick unit. That WILL fit onto the cooler unit since the thin fan is on the OUTside of this unit. It may take a little effort to get the spring clips that hold the fan onto the heatsink to fit the thicker fan. The real limit may be how much clear space there is near the cooler to allow a thicker fan, ESPECIALLY over the nearby RAM modules. In that line of thinking, one option would be a second unit of the 25 mm Scythe Kaze Flex II fan that is the other part of your system. Its specs are 53 CFM air flow and 0.97 mm water max backpressure. The Scythe web page promotes a feature that the thin fan rotates in the opposite direction from the thick one for better performance, but I doubt that is a huge factor, and would be out-done by simply using a higher-rated replacement.

There is a 25mm fan in the center of the heat sink, but the clips for the front fan definitely won't fit anything bigger than a 15mm fan. They only just barely work with the 15mm fan. A 25mm fan would probably fit on the front without interfering with the nearby RAM slots, but I'd have to get (or make) different clips in order to use one.

And yes, they do rotate in opposite directions. I think it's supposed to move the air around more between the fins of the heat sink, and also reduce noise from air turbulence. The front fan rotates counter-clockwise like the case fans, and the inside 25mm fan rotates clockwise, so any 'normal' 15mm fan will probably work.

A significant factor in heat removal capacity is dust accumulation between the fins of the heatsink. So when you take things apart for this, I suggest you ASLO remove the thicker fan in the middle and do your best to poke and blow out any dust you can before re-installing the fans.

That is good advice. And I did already do that to remove as much of the dust as I can get. One of these days I might pull the whole heat sink out and really blast it with an air compressor instead of just canned air, but I don't want to do that while it is inside the case.

This fan seems to have good specs. Higher airflow than the fan that came with the heat sink, and quieter, and not too expensive, and really good reviews:

https://www.amazon.com/quiet-Wings-120mm-BL039-Cooling/dp/B016XWZ5MQ/ref=asc_df_B016XWZ5MQ/?tag=&linkCode=df0&hvadid=319185484784&hvpos=&hvnetw=g&hvrand=16956289550101763719&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029749&hvtargid=pla-564321259911&ref=&adgrpid=63609080556&th=1

The 120mm Kaze Flex II slim that seems to be the same fan that came with the cooler is about $15..

 

[WilliamM2]

I hadn't looked at the fan specs, so I appreciate that info. Not having to worry about really high CFM makes things a little easier.


There is a 25mm fan in the center of the heat sink, but the clips for the front fan definitely won't fit anything bigger than a 15mm fan. They only just barely work with the 15mm fan. A 25mm fan would probably fit on the front without interfering with the nearby RAM slots, but I'd have to get (or make) different clips in order to use one.

And yes, they do rotate in opposite directions. I think it's supposed to move the air around more between the fins of the heat sink, and also reduce noise from air turbulence. The front fan rotates counter-clockwise like the case fans, and the inside 25mm fan rotates clockwise, so any 'normal' 15mm fan will probably work.


That is good advice. And I did already do that to remove as much of the dust as I can get. One of these days I might pull the whole heat sink out and really blast it with an air compressor instead of just canned air, but I don't want to do that while it is inside the case.

This fan seems to have good specs. Higher airflow than the fan that came with the heat sink, and quieter, and not too expensive, and really good reviews:

https://www.amazon.com/quiet-Wings-120mm-BL039-Cooling/dp/B016XWZ5MQ/ref=asc_df_B016XWZ5MQ/?tag=&linkCode=df0&hvadid=319185484784&hvpos=&hvnetw=g&hvrand=16956289550101763719&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029749&hvtargid=pla-564321259911&ref=&adgrpid=63609080556&th=1

The 120mm Kaze Flex II slim that seems to be the same fan that came with the cooler is about $15..

There should have been 2 extra 25mm fan clips for an optional third fan in the package. I also recommend the Arctic P120 PWM fans. I use one on my Mugen 5, Much better performance than the stock fans, more pressure, amd more airflow. Still silent. I'd replace them both.

Artic also gives you a 6 year warranty on tose fans.

 

[BoomerD]

I hadn't looked at the fan specs, so I appreciate that info. Not having to worry about really high CFM makes things a little easier.


There is a 25mm fan in the center of the heat sink, but the clips for the front fan definitely won't fit anything bigger than a 15mm fan. They only just barely work with the 15mm fan. A 25mm fan would probably fit on the front without interfering with the nearby RAM slots, but I'd have to get (or make) different clips in order to use one.

And yes, they do rotate in opposite directions. I think it's supposed to move the air around more between the fins of the heat sink, and also reduce noise from air turbulence. The front fan rotates counter-clockwise like the case fans, and the inside 25mm fan rotates clockwise, so any 'normal' 15mm fan will probably work.


That is good advice. And I did already do that to remove as much of the dust as I can get. One of these days I might pull the whole heat sink out and really blast it with an air compressor instead of just canned air, but I don't want to do that while it is inside the case.

This fan seems to have good specs. Higher airflow than the fan that came with the heat sink, and quieter, and not too expensive, and really good reviews:

https://www.amazon.com/quiet-Wings-120mm-BL039-Cooling/dp/B016XWZ5MQ/ref=asc_df_B016XWZ5MQ/?tag=&linkCode=df0&hvadid=319185484784&hvpos=&hvnetw=g&hvrand=16956289550101763719&hvpone=&hvptwo=&hvqmt=&hvdev=c&hvdvcmdl=&hvlocint=&hvlocphy=9029749&hvtargid=pla-564321259911&ref=&adgrpid=63609080556&th=1

The 120mm Kaze Flex II slim that seems to be the same fan that came with the cooler is about $15..

When I pulled my old Noctua NH-U12P SE2 cooler from my ancient system, In addition to giving the fans a thorough cleaning, I stuck the radiator fins in a bucket of hot, soapy water and let it soak for a bit...then, a thorough rinse with scalding hot water and a good blow-dry. It LOOKS as clean as brand-new. It's too bad really it isn't enough of a cooler for my i5-13600K. (I have requested the LGA 1700 mounting brackets though...we'll see how it does)

 

[Fardringle]

There should have been 2 extra 25mm fan clips for an optional third fan in the package. I also recommend the Arctic P120 PWM fans. I use one on my Mugen 5, Much better performance than the stock fans, more pressure, amd more airflow. Still silent. I'd replace them both.

Artic also gives you a 6 year warranty on tose fans.

I'll have to see if I still have the box somewhere, but I don't remember it including a third set of clips, although I do remember that it had a paper with a part number to order more clips if you want to add a third fan.

I know that Arctic lists a 6 year warranty on the fans, but when I tried to get my failed 140mm fans replaced, I had to ship the bad fans back in order to get replacements, and it just wasn't worth the cost.

edit: I do still have the box and it had a spare set of 25mm clips and a paper with instructions to order more, so I remembered the paper but forgot about the clips, so thank you for that suggestion!

 

[Paperdoc]

Yes, that beQuiet fan would do nicely. I have beQuiet fans in my system for case ventilation. I d0 not do heavy workloads, but these fans are very quiet for what I do with lots of reserve capacity for greater cooling. Glad you found those spare clips because I think the beQuiet unit is 25 mm thick.

 

[BoomerD]

Yes, that beQuiet fan would do nicely. I have beQuiet fans in my system for case ventilation. I d0 not do heavy workloads, but these fans are very quiet for what I do with lots of reserve capacity for greater cooling. Glad you found those spare clips because I think the beQuiet unit is 25 mm thick.

I have 3 be quiet! 140mm Silent Wings 3 fans in my Dark Base Pro 900 Rev.2 case. They are NEARLY silent. The numbers actually favor the Arctic Cooling fans slightly, (noise, CFM airflow, mm/h2o pressure) but not by much.

 

[Fardringle]

Thank you all for the input. I ordered a three pack of 25mm fans and will probably swap both of the fans on the cooler.

The 25mm fan in the middle of the cooler seems to be working fine still so I might put one new fan on the front first and test the performance, then swap both to see if the reversed direction of the current middle fan actually makes any noticeable difference in CPU temperatures.

 

[Fardringle]

I find it very interesting that replacing the dying front 15mm fan that I had capped at 700rpm to keep it from screaming, with a new 25mm fan with much higher airflow and a more normal control curve actually didn't seem to make any difference at all in CPU temps with the same 100% load.

Replacing the middle 25mm with a new 25mm fan may have reduced the CPU temps by maybe 1 or 2 degrees Celsius. So really not much difference at all.

But the computer is noticeably quieter now with that bad fan gone, and maybe even a bit more so with the second fan replaced, so that's a definite improvement!

 

[In2Photos]

I find it very interesting that replacing the dying front 15mm fan that I had capped at 700rpm to keep it from screaming, with a new 25mm fan with much higher airflow and a more normal control curve actually didn't seem to make any difference at all in CPU temps with the same 100% load.

Replacing the middle 25mm with a new 25mm fan may have reduced the CPU temps by maybe 1 or 2 degrees Celsius. So really not much difference at all.

But the computer is noticeably quieter now with that bad fan gone, and maybe even a bit more so with the second fan replaced, so that's a definite improvement!

That's actually not that uncommon. For air coolers the heatsink is doing the majority of the work as it's pulling the heat from the CPU. The air being passed over the heatsink just provides the heat transfer back to the air so that the case fans can expel it from the case. The quality of the base plate and number of heat pipes along with fin density matter more than the fan. The quality of the fan yields a better experience as you note due to noise.

 

[DasFox]

I’d say, next time you are in the market for parts, go with Noctua next.

Sure there are a lot of brands out there, I think these guys are the tops!

Noctua.at - Premium cooling components designed in Austria

Designed in Austria, Noctua's premium cooling components are renowned for their superb quietness, exceptional performance and thoroughgoing quality.

noctua.at

 

[BoomerD]

That's actually not that uncommon. For air coolers the heatsink is doing the majority of the work as it's pulling the heat from the CPU. The air being passed over the heatsink just provides the heat transfer back to the air so that the case fans can expel it from the case. The quality of the base plate and number of heat pipes along with fin density matter more than the fan. The quality of the fan yields a better experience as you note due to noise.

And, especially with air cooling, the ambient (room) air temperature is going to be the key to how much you can cool the CPU. (or ANY component for that matter)

 

[Paperdoc]

Bear in mind HOW the cooling unit for a CPU is controlled. We all talk about SPEED control, but it really is TEMPERATURE Control. The system has a target for what the measured temp (by a sensor inside the CPU chip) should be, and it adjusts the fan speed to whatever it takes to keep that value close to its target. So installing a fan with greater air flow capacity actually means that the fan SPEED will be slower than the old fan's to achieve virtually the SAME TEMPERATURE! So, to evaluate the impact of the new fan, do NOT look at the temp; check the fan speed.