I have the well-known noisy fan problem with my Corsair TX650 V2. I have now had the PSU for exactly a year, so no hope of returning it. I nearly returned it when I bought it but decided to put up with the noise, but now I have had to move my case to sitting on my desk, the noise is unbearable. It's a shame because I bought quiet components for the rest of my PC, and all my other fans are almost silent.

Unfortunately I cannot afford to change the PSU, so I want to try and change the fan to something else. I won't have a problem doing that but am unsure which fan to buy, and also how much of the problem is the fan's controller. I could always add a variable resister between the fan and PSU, that maybe I could get to externally? I'd rather just change the fan though and be done with it though.

Can anyone recommend a suitable fan for this particular PSU please, that would work with the PSU's own speed controller (if it even has one)?
Thanks.

The fan controller is certainly a big part of the problem, Most fans in most quiet PSUs are actually quite noisy at full speed; it's the smart controller which keeps the fan from running so fast when it doesn't have to.

So yes, you could just stick a resistor in line to reduce the voltage to the fan (which I think for that series was still a 2-line simple voltage controlled motor). How quiet (and smooth) this sounds will depend on the fan of course, and you might have to play with the exact resistor value to get the right speed -- ie to have it turn on consistently.

If replacing the fan altogether, you want something with a known low start speed and not more than ~1500rpm max speed. Perhaps 1200. But this depends partly on what the default min voltage to the fan is. You might want to measure that (across the fan terminals with a multimeter) to be sure. If you choose to do so, take great care with exposed wiring, as a live PSU can certainly ZAP you pretty good.

Thanks for your helpful response MikeC. I suppose that if I was to use a different fan that was quieter but moved less air at minimum speeds, then if the PSU become too hot, it should increase the speed more. As long as the maximum speed was adequate to keep things cool, then I at least won't be any worse off.

I have read in another thread that someone used a 1200rpm fan, but I didn't want to just go by one person's experiences. So it helps a lot that you agree with that number. That person also said that the fan in the TX650 is 135mm rather than the advertised 140mm, but I've looked up the one he mentioned (which is no longer made unfortunately) and it did have holes the same as a 140mm fan would, so I can only assume that any 140mm fan would fit.

I think I would rather try a new fan first before experimenting using a resistor or external potentiometer to control things. To save me taking my PSU apart (which is quite an effort as I have all the cabling tied down very neatly inside the PC case) twice, I'll just find a fan that advertises itself having a low start voltage and hope it'll do, rather than taking it apart to measure that voltage first.

Off to do some fan research next! Oh and thanks for the safety tip, it's always good to be extra careful with PSU's. I'm an ex electronics engineer so know what I'm doing, but I would recommend anyone who hasn't done such things before to take great care.

Yes, I'm the one with the Scythe Kama Flex in the Corsair TX650 V2; the original fan model# is D14BH-12. The info on the net about this fan is contradictory, according to Yate Loon the max RPM is 1800, some other reviews say 2300 or 2800 - so take your pick. IMO the RPM is around 2800, because I "feel" it close to a Scythe Kaze Ultra 3000 RPM at maximum RPM. It starts reliable on 5V as I've tested, some reports on the net mention 4.35V; tomorrow I will try to measure the start-up voltage, and come back with the value. And I hope that my info helped

I appreciate you writing, thanks. I've been doing more research on this since writing here last, and a few different people have recommended the Be Quiet! SilentWings 2 BL063 fan for their TX750 V2. On the Corsair forums someone also said the fan used in that is the same Yate Loon as you said is in the TX650. I wouldn't worry too much about testing the start-up voltage, as the SilentWings 2 starts at 4V I think it was (I forget the exact number), which must be adequate. If you've already done it though it would be nice to know what reading you had.

I'm going to look at other fans today too and make a decision on which to buy. I've made myself a nice list of all the criteria to take into account. Being in the UK, some of the fans mentioned by people (possibly the one you use) as a replacement aren't available to me, but the SilentWings is at least.

Yes your info has been very helpful, thank you!

[Edit] On the Yate Loon website, it shows the D14BH as being 2800RPM, so maybe they've updated their information?

Just a quick update - I've now ordered the Be Quiet SilentWings 2 BL063 140mm fan.

I've looked at others that have been suggested, and looked through 2 or 3 "quiet fan round-ups" and gone through all my options. Of those available to me in the UK, the SilentWings 2 seemed about the best. I'm a bit bothered that it only runs at 1000rpm, but at that speed it moves more air than one of the other good options running at 1200rpm, and it's about 5dBA quieter. So I hope it's the right choice for me.

I found one of the limiting factors of many popular quiet fans was that their starting voltage wasn't low enough, so I'm grateful to everyone (this thread and in other forums) who have told me that the starting voltage is important for a PSU fan.

First, the measured start-up voltage: 3.92-3.95V, depending on the position(horizontal or vertical), so it's safe to assume 4.0V as general start-up voltage.
Yate Loon RPM confusion: the 140mm and the 135mm series carries the same part #'s:
http://www.yateloon.com/en/2_1356_58938/product/DC_FAN_SERIES_id38839.html
http://www.yateloon.com/en/2_1356_58938/product/DC_FAN_SERIES_id330979.html
The D14BH-12 is listed with 1800 and 2800 max. RPM, depending on size.
Today I measured the dimensions of my fan - it's a 140mm unit so I stand corrected; I don't know from where I draw my ideas about the 135mm only fan(maybe wrong dimension measurement a year ago?); thank you for "pushing me" to take out&measure the old fan.
I hope that your new fan will serve you for the best

Thanks for the info Zolishoru. That is a very low voltage for start-up, right on the limit of my new fan's capability.

As for fan size - I don't claim to be an expert in fans at all, but from my research lately I've found that often the fan size itself is less than 140mm, and the 140mm refers to the mounting. I will happily stand corrected though if this is not generally the case.

I'm sitting waiting for my new fan to arrive and am worried about its slow rotational speed. It's only 1000rpm, and with 4V start-up it's obviously going to be very slow. I hope the PSU uses a feedback system to speed up the fan if needed, rather than supplying a certain fixed voltage to fit the temperature - I would have thought it would. So if my new fan doesn't cool it enough, I trust the PSU will up the voltage more. I'm actually considering connecting the fan externally to a molex, so it's always running at full speed (this should still be very quiet). If I don't do that, I think I may at least run the RPM sense wire out of the PSU and connect it to the PSU_FAN header on my mobo, so I can monitor the speed. Would there still be a return path for that signal though even without connecting the black fan wire to the same header? Hmmm.....I'm thinking aloud here!

I'm looking forward to experimenting with this.

The controller definitely raises and lowers voltage in response to an internal temp sensor, but it's got to be designed with a particular fan, not any fan. If a controller/fan combo is set up for very aggressive cooling (like your TX650 was), a slower fan should work, but I would worry too about swapping in a 1000rpm fan in place of a 2800rpm fan. That's a huge difference. I would not have gone for much less than 1500rpm fan knowing what you do about the original fan.

My thinking was that if it will keep on raising the fan speed until it reaches the required temperature, rather than just supplying the voltage needed for the original fan (so a guess in other words), then a new slower fan should be sufficient. I did do a lot of research on which fan to buy and it's very limited due to needing a low start-up voltage. Once the new one arrived in the post earlier though I did have serious thoughts of maybe using it as a case fan instead and purchasing something else for the PSU!

Anyway, I have it fitted now. I wish they would make the fittings completely standard! Anyway, I've just started it up and I can barely hear a thing. So far, I'm very pleased, and I'm leaving the side panel of the case off so I can keep an eye on things. I can't tell how fast the new fan is spinning but it's going a fair bit faster than my rear case fan which is running at 500rpm at the moment, so I would guess it's running at at least 800rpm.

I have the speed sense wire from the new fan poking out of the PSU case and tied up safely for now, and I may hook that up to the PSU_FAN header at some point and see if that'll give me RPM without a 0V on the same header.

Well, the fact that your new fan is running in the PSU is a very good thing -- I'd say 90% success.

You'll know in the long run whether it provides enough cooling -- ie, if your PSU suffers overheating damage... but unless you're always gaming with a hot video card in hot weather, you should be fine.

The RPM sense output on the fans are open-collector type; to work properly, you need common ground between the fan and the MB(no control circuit between the fan and ground). Check if you have 0 ohms or close between the negative fan lead and the general PSU ground; alternately, you can check the DC voltage on the sense wire on the powered PSU; if it's more then 0.2V, then you have control circuit between the fan and the ground - no reliable RPM sensing is possible without level translation. And I would do the test before I connect the speed wire to the MB

Ok, I think I'll just leave that for now. It looks to be running ok and I don't feel any warmth in the PSU at all.

Thanks for your help with this.

Hi, just connecting the rpm wire to the motherboard header will work just fine! Well it has for me in several cases anyway. The whole PC system has a shared ground, which I think is why it works.

When I've done it I've kept the rpm wire in the plug so connects straight on no problems at all.

My take on chnaging the fan for a slower one is it's quite safe for the PSU as the fan controller will keep increasing the fan speed. You end up, for example, with "normal" PSU internal temp for ~300w but with only 200w load applied. The only time you'll get issues is if the swapped fan has been taken to full speed and it's still not enough.

The only time I've had this is with my 650w Antec Signature that should have a ~4000rpm 80mm fan in it and now has ~2000rpm fan, I was driving i7-2600k @ 4.5GHz with GTX560 Ti, GTX285 and GTX260 all running folding@home. The power draw from the wall was over 500w and the PSU fan speed reached pretty much maximum! Kept on working though...

Regards, Seb

That's all interesting stuff Seb and good to know, thanks for your post.

I'm not a big gamer, just now and then I do a bit. I only have a GTX460 at the moment and my CPU is thr i5 2500K (OC'd to 4.6GHz), so I'm not stretching the TX650 PSU at all. I chose it a year ago so it was future-proof.

So at least for now I don't think I'll worry.