Would you want a 4-pin PWM to 3-pin fan converter?

[just brew it!]

Pretty much all modern motherboards have PWM fan headers for the CPU, but the selection of aftermarket fans -- especially 80mm and up -- with a 4-pin PWM connector and ball bearings on them leaves something to be desired. Many of the ones that *are* out there apparently use sleeve bearings, which makes me a little nervous on something that is so critical to keeping your CPU temps under control (sleeve bearings have a rather limited lifetime).

I'd really rather mate a fan of my own choosing to a large heatpipe cooler; but then I'd be giving up the fan speed control.

I'm toying with the idea of designing a device that converts a 4-pin PWM fan header to drive a conventional 3-pin fan, by using the PWM signal to control the voltage being fed to the fan. This way you could use pretty much any fan you want, without giving up the ability of your motherboard to control the fan speed.

I'm probably gonna at least pursue this for my own use/edification regardless of what other people think, but it occurred to me that there might be a viable product idea here.

[Dirge]

Yea that would be cool, especially if it is simple to assemble for those of us who lack a certain finesse when it comes to soldering . Is there any easy way to identify the type of bearing used in a fan? I have also come across a maglev type and wonder how good they might be... one would assume minimal wear and tear.

[thegleek]

If this ever comes to fruition, JBI, remember that I was the only one who voted for giving you a 6-pack of craft beer!

[Aphasia]

Thats actually a very good idea, although depending on which cooler is being used I can see an issue to who would use it. The last cooler I got has a external speed controller and 3-pin. It's the coolermaster V8, my last thermalright I just used pabst-fans and forget about controlling them thanks to the issue you just took up.

If you ever design one it would probably be cost-prohibitive to ship overseas, but if possible I could roll my own from a schematic/layout/component-list with little trouble.

[morphine]

I very much approve of the idea, but however I wouldn't see myself paying more than 1-2€ for one, because otherwise I'd just look for different fans altogether.

[just brew it!]

If this ever comes to fruition, JBI, remember that I was the only one who voted for giving you a 6-pack of craft beer!

Not the only one any more, just the first!

I very much approve of the idea, but however I wouldn't see myself paying more than 1-2€ for one, because otherwise I'd just look for different fans altogether.

That was my initial thought as well; then I started looking around at what's available out there in 92mm PWM ball bearing fans. Answer seems to be "not much". At least the 92mm Scythe KAMA-Flex PWM has S-FDB bearings, which should (theoretically) have a comparable service lifetime.

[just brew it!]

Is there any easy way to identify the type of bearing used in a fan?

Usually it will be listed in the specifications, either on the web site of the retailer or on the manufacturer's web site. If the type of bearing isn't specified it is probably sleeve; pretty much any *other* type of bearing -- ball or any of the FDB variants like S-FDB, hydro-wave, etc. -- is a desirable feature, so sellers tend to mention it.

I have also come across a maglev type and wonder how good they might be... one would assume minimal wear and tear.

There was a lot of hype about that tech a few years ago; I forget the name of the company that was making them. IIRC the first production run suffered from some sort of quality issue (motor tended to overheat or something...?), and I haven't heard anything about them since. Anyone know if they're still around?

Edit: On second thought, it is possible that I am actually thinking of "tip driven" fans, where the motor is in the perimeter of the housing (and drives the tips of the blades), instead of in the hub...

[Starfalcon]

Yeah, that is the one you are thinking of, and they had massive quality issues with early failure. They pretty much died off as quickly as they came out. Rather similar to the old kenwood 72X drives..they didn't live up to the sales hype.