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View Full Version : TMD fans that do not work, here is what to try


N8-sp
08-06-02, 12:15 PM
I recently ordered a Swiftech MCX4000 w/ TMD 37 CFM fan. The fan does not turn on when the system is powered up. The blades jiggle back and forth a few millimeters for several seconds, then stop moving entirely. I tried hooking it up to several motherboard headers, and it does not work on any of them. I even tried an adapter to hook it up to a standard 4 wire plug and it does not work.

If you start to turn the blades with your finger while the system is powered up, it will start turning, but makes a grinding noise for several seconds. Even while it gets started by this method, the fan RPM does not report in the bios.

In addition, the CPU temperatures soar into the 70 C + range while the fan is running once I 'finger-start' it. I do not think that this fan is putting out full CFM values.

I attached a 40 CFM Panaflo 80mm fan, and temperatures stay around 50C full load, so I know that this 37 CFM TMD fan is not working properly at all.

I did some additional testing on the TMD fan yesterday. When it is not attached to the heatsink, it works fine. When it is not attached to the heatsink and has the stock zinc-coated-steel bolts in the four holes, it works fine. When it is attached to the heatsink with normal tightness, it does NOT work. When attached to the heatsink very very loosely, it does work, but it is very loose and not safe to keep running like that.

It seems the bolts are grounding out the windings in the corner magnets, either from being too tight and creating some magnetic dampening or causing the TMD fan casing to touch the windings and ground out. There is not much room between the windings and the fan casing. When the bolts are tightened to normal tightness, the fan can start moving if I use my finger to get it started, but the metal fan casing gets very hot, like the current is grounding out through the frame into the bolts.

I found some brass bolts that are the same length as stock (2"). These brass bolts are the kind with the tapered shoulder at the head, not a flat base. This prevents the fan casing from being squished down while tightening. Anyway, the fan works just fine now while tightened all the way on the heatsink. I don't know for sure if it is the design of the shoulder, or the bolts being brass, or both these facts. I wanted to use nylon bolts, but couldn't find any at the time, so I just used brass. I think nylon would work the best, however.

SBeaver
08-06-02, 07:53 PM
That's good to know, I havn't heard much real info about the TMD's at all.
Maybe the heatsinkmakers made a mistake with the wrong type of bolts, hopefully changed now though as I hav'nt seen anyone else with this

rlemieux
08-06-02, 07:57 PM
I had no problems with mine and the regular bolts and noone else I have talked to has mentioned this.

hellrazrblade
08-06-02, 08:58 PM
one other option, is it possible that the blades or something are binding when you tighten it down and not the magnets?

SBeaver
08-06-02, 09:01 PM
Originally posted by hellrazrblade
one other option, is it possible that the blades or something are binding when you tighten it down and not the magnets?

Possible, but he said if he pushed it it sounded bad but then went back to full speed didnt he?
I don't think he's that stupid

Colin
08-06-02, 10:52 PM
N8-sp - Why don't you just get a replacement fan from Swiftech? I know from personal experience their customer service is superb.

N8-sp
08-07-02, 11:02 AM
I bought the combo from The Heatsink Factory. They have offered to replace it or give me a refund, but since it works right now, I am not worried about doing that - it is only $10. It would be more hassle for me to deal with replacing it than I care about. I am just waiting for the 80mm TMD versions to come out later this month anyway, and I will get one of those instead.

The Heatsink Factory has gotten several people that have this problem, and I have read on other forums quite a few people have this problem as well. It seems the first 'batch' of fans have this problem. I think it is a YS-Tech manufacturing issue that they have resolved by now. There is probably some insulating layer on top of the windings in the newer versions, would be my guess.

rlemieux
08-07-02, 12:39 PM
I got mine about a week before they were released to the public, and I have had no problems, but again I could just be lucky:)