may i ask why it has to be a ball bearing fan and not a sleeve bearing?mathias wrote:No, I don't actually want any tricools, plus that's in australia. I'm probably going to get a P180 anyway. If someone in Canada was selling a BQE stock fan, or some other ~1300rpm ball bearing fan. then it would be my lucky day. Or if someone toronto was selling a P180 bundled with some other good fans.
Another Ball vs Sleeve Bearing discussion
Moderators: NeilBlanchard, Ralf Hutter, sthayashi, Lawrence Lee
Orientation definitly does have some kind of effect, switching it requires the fan to wear in again. Papsts' sleeve bearing are sturdier than normal. The review of the revised S12 mentions the improved reliability of ball mearing fans in such PSU.Aris wrote:i have a sleeve bearing papst 120mm fan inside my seasonic psu, and its mounted flat. i dont really see how the fans orientation makes any difference.
On the other hand, a 12cm sleeve bearing fan in a PSU would also be worn out additionaly by exhausting system heat. Maybe it's hardly an issue, there are PSU's that use D12SH's(2200rpm yate loon). It should be easy to test how valid that concern is by putting a high speed sleeve bearing fan flat in a box with a specific temperature and seeing how long it'll run.
i have a feeling if you did that test we wouldnt hear back from you for a few years.
everyone knows ball bearings last longer, thats why they exist alongside sleeve bearing fans. but i think your getting hung up on the term "longer". longer meaning it will last 10 years instead of say 7 or 8 years. trust me when i say, you will have long forgot about your fan before it ever starts to reach its point of failure.
ball bearing fans are needed for industrial useage, where the environment isnt the best and it will need to run 24/7 for many many many years. in places where if it fails it could cause major damage and/or loss of equipment.
now think about your home pc. chances are your gunna replace either it or that fan in less than 5 years. and even if you dont, and even IF you happen to have it long enough for it to fail, whats going to happen? your computer crash's, you notice the fans bad, you replace it and you boot it right back up, no harm done cause almost every single piece of hardware made today for pc's has thermal limits that cause the computer to shut down before any perminant damage is caused.
everyone knows ball bearings last longer, thats why they exist alongside sleeve bearing fans. but i think your getting hung up on the term "longer". longer meaning it will last 10 years instead of say 7 or 8 years. trust me when i say, you will have long forgot about your fan before it ever starts to reach its point of failure.
ball bearing fans are needed for industrial useage, where the environment isnt the best and it will need to run 24/7 for many many many years. in places where if it fails it could cause major damage and/or loss of equipment.
now think about your home pc. chances are your gunna replace either it or that fan in less than 5 years. and even if you dont, and even IF you happen to have it long enough for it to fail, whats going to happen? your computer crash's, you notice the fans bad, you replace it and you boot it right back up, no harm done cause almost every single piece of hardware made today for pc's has thermal limits that cause the computer to shut down before any perminant damage is caused.
That's why it would be a good idea to simulate bad conditions. Make that some of the worst conditions imaginable if you want, like SLI 6800ultras, an overvolted presscot and a really bad exhaust grill, on a really hot day, I think all that heat going through a high speed sleeve bearing fan in a horizontal position would kill it pretty soon.Aris wrote:i have a feeling if you did that test we wouldnt hear back from you for a few years.
I'm not getting hung up on the general durability of sleeve bearings. Just that if a sleeve bearing fan is mounted flat, the bearing lubricant tends to sink to the bottom. I forgot about how exhausting system heat makes a difference(somehow causes the lubricant to get centrifuged more).
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Aleksi
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Those figures aren't exactly the best ones, actually not even close to the truth if you're speaking about generic fans. A spec called L10 is used when talking about fans instead of MTBF:Aris wrote: everyone knows ball bearings last longer, thats why they exist alongside sleeve bearing fans. but i think your getting hung up on the term "longer". longer meaning it will last 10 years instead of say 7 or 8 years.
L10...
- L10 is when 90% of fans are still running & in specification
- Exact figure varies per size, rpm, bearing type, temperature
L10 is the only acceptable metric for fans...
o EBM-Papst -- L10 based on Field & HALT testing
o NMB-MAT -- L10 based on HALT testing alone
MTBF is not an acceptable metric for fans...
- MTBF of bearings is unrepresentatively long for a fan
---- FB bearing data is 376k-hrs @ 70oC, 1,000k-hrs @ 55oC
---- those are NOT the figures once assembled into a fan
A normal PC exposes the CPU & PSU fan to air temp of 40oC
- 40oC Panaflo FB L10 = 6yrs by spec, 9yrs by field data
- 40oC NMB-MAT R L10 = 8yrs, 10yrs by field data
- 40oC Papst BB L10 = 9yrs, 11yrs by field data
A silent PC exposes the CPU & PSU fan to air temp of up to 70oC
- 70oC Adda L10 = 5 months by spec (4468hrs), 6 months by field data
- 70oC Panaflo FB L10 = 4yrs by spec, 7yrs by field data
- 70oC NMB-MAT R L10 = 7yrs by spec, 9yrs by field data (their real benefit)
- 70oC Papst BB L10 = 6-7yrs by spec, 9yrs by field data (their real
benefit)
Quite a difference? The 70C is a bit high figure, but it's there just to give perspective.
Probably the most long lasting sleeve bearing one can find is the Papst. However even Papst gives different L10 specs for when the fan is placed horizontal (~6-9 years at 25C, IIRC) and vertical. Simply because placing a sleeve bearing fan horizontally eats away at the bearing.
I've seen office and manufacturing plant PCs that have had ball bearing PSU fans (I know their ball bearing, I have a habbit of checking fans everywhere...
Actually those have been ADDAs quite often, but that might due to the buying one type of PSUs and PSU manufacturer is using just those.) where the have simply refused to start up after the PC has been turned off. And some of these PCs aren't even old, some are as new as 1-2 years. But in all honesty, there are some ~5-6 year old PCs that are ticking even still.Personally I have a bad experience when using a sleeve bearing fan in a PSU. Most likely the fan had been sitting in a storage somewhere, and after installing it was OK for a month or so, but it's making quite a racket by now and it's getting louder day by day.
I've been moving towards only using Panaflos, NMB's and Papsts as PSU and CPU (and case if possible) fans,. My point with my yadda yadda is, that I may well end up giving my computer to a relative after a few years and I truly don't want them calling me saying "the PSU fan isn't spinning and CPU is fried for some reason?". That being said, I understand that most users on SPCR swap their fans, cases and components few times a year, yearly or once in two years so that isn't a disaster when it happens to us.
But those kind of lifetime figures stated in this thread simply aren't realistical by any means.
EDIT: Sorry Ralf for the thread hijacking.
Someone buy Ralfie's P180!
EDIT2: Added some info about L10
idunno, even by your data my "estimates" seem pretty close to the truth
if you have a system with ambient internal temps above 40c then you have some major issue's. personally my case temps are usually around 30-35c at the most in the summer time.
and looking at your L10 data, my estimates were right on for that temperature range.
just cause your CPU die gets 70c or hotter, the air around it isnt. and the fan is in the air not physically attatched to the cpu die.
so field data says you'll only get 9 years instead of 10 or 11 years with ball bearings. think about what computer was top of the line 9 years ago. 200mhz processors and edo memory. just cause you've had a few bad seeds doesnt mean that all sleeve bearings in the world are crap and will die in a few months. no product is without faults, i'm sure if you ask around you'll find story's of ball bearing fans failing in just a few months.
if you have a system with ambient internal temps above 40c then you have some major issue's. personally my case temps are usually around 30-35c at the most in the summer time.
and looking at your L10 data, my estimates were right on for that temperature range.
just cause your CPU die gets 70c or hotter, the air around it isnt. and the fan is in the air not physically attatched to the cpu die.
so field data says you'll only get 9 years instead of 10 or 11 years with ball bearings. think about what computer was top of the line 9 years ago. 200mhz processors and edo memory. just cause you've had a few bad seeds doesnt mean that all sleeve bearings in the world are crap and will die in a few months. no product is without faults, i'm sure if you ask around you'll find story's of ball bearing fans failing in just a few months.
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Aleksi
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Aris, you really didn't get my point.
That 40C isn't that far fetched when inside a computer. Search the forums for PSU exhaust temps, they can easily be around 40C-50C. And like I said, that 70C was over the top but I used that temperature, because those figures are readily available at that temp.,
I don't want to use either sleeve OR ball bearing fans in a hot environment like the PSU or CPU, if they are not made by a tier-1 fan maker like Papst, Panaflo etc... because according the hard data they simply do not last in a hot environment. Just by looking at the data, you can see there is a big difference between a generic like ADDA and proper industrial grade fan like Panaflo or Papst.
I have nothing against sleeve bearings, I've used a Papst Sintec sleeve bearing in my PSU, just like you. I sold this PSU to a friend, but I definately would have not sold it as it was if I had stuck some generic sleeve bearing fan in it.
That 40C isn't that far fetched when inside a computer. Search the forums for PSU exhaust temps, they can easily be around 40C-50C. And like I said, that 70C was over the top but I used that temperature, because those figures are readily available at that temp.,
I don't want to use either sleeve OR ball bearing fans in a hot environment like the PSU or CPU, if they are not made by a tier-1 fan maker like Papst, Panaflo etc... because according the hard data they simply do not last in a hot environment. Just by looking at the data, you can see there is a big difference between a generic like ADDA and proper industrial grade fan like Panaflo or Papst.
I have nothing against sleeve bearings, I've used a Papst Sintec sleeve bearing in my PSU, just like you. I sold this PSU to a friend, but I definately would have not sold it as it was if I had stuck some generic sleeve bearing fan in it.
The D12SH that I pulled from a fortorn looked like it was tweaked for high speed, it had a big hub(and only 5 blades). But the D12SH in the new 500w nexus PSU apparantly uses the same impeller as some D12SM's and D12SL's and so has a rather small hub.
At least no PSU's have horizontally placed exhaust fans, which would have both those problems reducing their lifespan, except for the clever power units with the radial fans.
At least no PSU's have horizontally placed exhaust fans, which would have both those problems reducing their lifespan, except for the clever power units with the radial fans.
That all depends on where you live. Where I am gets 35-40c shade temperature in summer, cooling down to 20-30c at night. Obviously if the ambient air temperature is 40c then the case temp with be ~50c in a cool PC.Aris wrote:if you have a system with ambient internal temps above 40c then you have some major issue's. personally my case temps are usually around 30-35c at the most in the summer time.
The humidity is high where I am as well, but no where near as bad as in Malaysia, etc. I would like to see some tests on components in high temp high humidity environments, but everyone seems to assume your in an 25c air-conditioned office.