----- Original Message -----
From: "peter nikolic"
Hi ..
Right now this may be something that bugs a lot of you Video card fans
I run Nvidia FX5500 video cards in all my machines (i happenb to like them) and the price is right ..
but one thing that bugs the living daylights out of me is the short life span of the fans i have 4 machines all with what boils down to the same video card in just under different brand names .. so it is not one maker at fault it is the lot .
What lubrication do any of you use to shut the darn things up i have tried WD40 ,Duck oil (another type of WD40) , 3in1 oil , sewing machine oil diluted engine oil puse many others and none of them last much more than a month or 2 then back to squealing squeaking ratteling when a 4 boxes start we .. ..
First: 3in1, wd40, etc are all not suitable for any sort of motor because they dry out. Engine oil is not suitable for any electric motor primarily because it is loaded with detergents that gum up (car engines whare this oil is designed to be used are a completely different animal) and clog sleeve material. Sewing machine oil was the closest to correct, correct being 20w (or lighter in this case) non-detergent. Except, Second: Really there is no correct lubricant for this. You can not lubricate a fan (or any other electric motor, or more correctly, any bearing) to make it work once it has gone. In the case of sleeve bearings, the sleeve is a porous material and the factory lubricant wicks from the outside of the bearing, through the porous copper-looking sleeve, to the shaft. once they dry out that's it. no fix. The shaft wears the inner sleeve surface which closes up all the microscopic openings the oil used to soak through. It's also possible for the shaft to wear the bearing surface and close the pores even before the oil has dried out if the bearing is of low quality or the impeller is not well balanced. When you oil it, you are just putting a little oil on the shaft directly, which quickly goes away. There is no way to make it stay there. You can try exotic lubricants that cling and resist drying out or wearing off, maybe things impregnated with teflon, and they'll maybe run a little longer than plain oil in that case, but nothing will actually work. In the case of ball bearings, there is no porpus sleeve, but there is two other sorts of mechanical wear that can't be fixed and the bearing will never work again for any length of time once that happens. once the balls and the races get the slightes bit deformed thats it. on top of that, the seal or shield that keeps out dust and keeps in the factory lubricant gets worn from the shaft rattling around and becomes too open to keep dust out or lubricant in any more so even if you flushed it out and packed in some new grease, it will just leake out and get contaminated with dust practically immediately. In short, lubricating a worn bearing is useful only as an emergency measure for keeping a server's cpu running for a few days while you go find a new fan. (or in some exotic cases, new bearings for the fan.) The only fixes are: a) use higher quality fans, That is, ones that have longer expected life time ratingt (mtbf). It's a spec you can look at when looking at fans from fan manufacturers just like speed or size. The way a fan can be higher quality is just higher quality bearings, more carefully balanced impeller, dual ball bearing design. b) use larger, slower fans. c) use larger heat sinks and no fans At least one company makes fans with air bearings. no lubricant. They are supposed to be able to spin faster and still last a long time. (and also be really quiet while doing so) I have no experience with them directly. I have a couple big slow ones but they are big, slow, and still new, so not useful for saying if tiny fast ones will last a long time on a vga card. But they are supposedly used in laptops and other places where thats exactly the problem is needing a tiny, fast fan that doesn't wear out in a week. Maybe tiny fast fans are where air bearings work best actually, considering the viscosity of air. In a previous life I repaired all manner of electric motors from power tools to huge pumps. -- Brian K. White brian@aljex.com http://www.myspace.com/KEYofR +++++[>+++[>+++++>+++++++<<-]<-]>>+.>.+++++.+++++++.-.[>+<---]>++. filePro BBx Linux SCO FreeBSD #callahans Satriani Filk! -- To unsubscribe, e-mail: opensuse+unsubscribe@opensuse.org For additional commands, e-mail: opensuse+help@opensuse.org