[SOLVED] Strange case fan

[Adrian_19]

I just bought 2 floston ice15 case fans and mounted them on my case. The problem is that they're always running at full speed no matter what i do. I tried changing the profile from bios, i tried with speedfan, nothing works. It is connected to the motherboard with the 3-pin and not with the molex. The other strange thing is the fact that monitoring shows its speed go up to 19600 rpm for a second and then come back down. Its max speed is 1300 rpm but its constantly at 1570 rpm, sometimes even going up to 3000. I have no idea what to do anymore. Can anyone help me?

 

[ron2456]

Those are certainly not the best fan. To make the fan to run at 19600 rom for a minute the mobo needs to supply more than 2A of current. So I would say faulty fans or already damaged mobo.

 

[Adrian_19]

Those are certainly not the best fan. To make the fan to run at 19600 rom for a minute the mobo needs to supply more than 2A of current. So I would say faulty fans or already damaged mobo.

Yeah i know they're not the best but they were cheap so i thought i'd try them out. The cpu fan or the previous case fan speeds are fine and monitoring shows they work as intended so i don't think it would be the motherboard. It's just curious how both of them are the same. The reviews were mostly good so i didn't think i would encounter any problem.
P.S.: new max speed: 57000 RPM showed on monitoring

 

[the nerd 389]

As said above, those are not particularly good fans. I'd expect to have trouble with the tachometer (RPM sensor) on them out of the box, to be honest. A glitchy tach can result in the speed sensor spontaneously reading speeds much higher or lower than what the fan is actually spinning at.

If you're using DC speed control, be aware that the mechanism that boards use to accomplish this will interfere with the speed sensor as well. This usually has similar symptoms to a faulty tach, but the glitches are much more frequent with DC speed control.

Note that if the fan actually speeds up to 3000 RPM, it will sound like a jet engine. If it sounds the same, it's just a tach glitch. If it sounds like a jet engine, there's something horribly wrong.

 

[ron2456]

Those are certainly not the best fan. To make the fan to run at 19600 rom for a minute the mobo needs to supply more than 2A of current. So I would say faulty fans or already damaged mobo.

Yeah i know they're not the best but they were cheap so i thought i'd try them out. The cpu fan or the previous case fan speeds are fine and monitoring shows they work as intended so i don't think it would be the motherboard. It's just curious how both of them are the same. The reviews were mostly good so i didn't think i would encounter any problem.
P.S.: new max speed: 57000 RPM showed on monitoring

Seriously, why bother with them. They are trash and before they damage the pc get someting better.
I just bough a pair of Sickleflow X and they aare pretty good and cheap at 10$ a piece. be sure to get the X version as its better.

 

[the nerd 389]

Seriously, why bother with them. They are trash and before they damage the pc get someting better.
I just bough a pair of Sickleflow X and they aare pretty good and cheap at 10$ a piece. be sure to get the X version as its better.

Cheap fans have their place, even if you wouldn't get them for yourself. In practice, even those cheap fans can be fairly reliable if they're set up for redundancy (which they are in most cases, as you really only need one fan to prevent damage).

With that said, the speed control -> RPM interference issue is intrinsic to the 3-pin connector. No matter how expensive the fan, it will have that issue when run off of DC/voltage speed control.

A broken tach would be a different issue, though. That only happens on the cheap ones.

 

[Adrian_19]

Seriously, why bother with them. They are trash and before they damage the pc get someting better.
I just bough a pair of Sickleflow X and they aare pretty good and cheap at 10$ a piece. be sure to get the X version as its better.

Cheap fans have their place, even if you wouldn't get them for yourself. In practice, even those cheap fans can be fairly reliable if they're set up for redundancy (which they are in most cases, as you really only need one fan to prevent damage).

With that said, the speed control -> RPM interference issue is intrinsic to the 3-pin connector. No matter how expensive the fan, it will have that issue when run off of DC/voltage speed control.

A broken tach would be a different issue, though. That only happens on the cheap ones.

I would return them if i could. They are made of very cheap plastic and it cracked at every screw hole when i screwed them in.
Anyway, another thing i noticed is that one fan runs at lower speeds ~ 1350 rpm than the other that runs at 1570.