First just wanted to say that this is an amazing site and I wish I'd found it before getting my current system! I've spent some time flicking through the resource material so I hope this query doesn't sound too silly...

About a week ago I took receipt of the following system:

Fractal Define R4 mid-tower case
ASUS P8Z77-V LX mobo
Intel Core i5 3570 (not overclocked)
NZXT Havik 140 cooler
ASUS GeForce GTX 660 Ti
8 GB corsair vengeance RAM (tried to get some that were lower clearance and did not have the fins)
Seasonsic bronze M12II 750w PSU (yes this is overkill at the moment but I am happy with the noise levels)
Intel 335 240GB SSD
WD Caviar Blue 1TB
ASUS Xonar DSX

Since I don't really have the time to put systems together myself I had someone else build it made the mistake of getting the Havik 140 cooler without doing proper research about the best noise-reduction option.

I've been running the system for a week now and have found that the Havik is worryingly loud (much louder than my previous system which was built around an Antec P183 and a megahelms heatsink and was very quiet indeed). I've taken the case sides off and tried briefly shutting off the various fans to narrow down the noise (which is both loud in terms of the fans themselves and the air they are pushing through). The case fan itself is very quiet, and using the toggle switch on the front of the case to reduce the case fan voltage to 5v or 7v has no real impact. The PSU and the graphics card are also very quiet.

I've read the website's review for the Havik 140 which noted that it is ok with one fan but starts to get loud when the second is added. Given that the rear case fan is sitting no more than about 10cm from one of the fans it seems almost overkill to have all three sitting there blasting through air, which could also be accounting for the sound. In any event I have a few steps I plan to go through and the reason for my post is to get some feedback, if possible, about what the best option is likely to be:

1) I can try and find a utility to reduce the speed of the CPU fans down from full voltage to somewhere around 7-9v and see if that makes a different. The motherboard doesn't support the ASUS fan utility apparently so will need to be a third-party software item. I'm a little hesitant to play with this as I am not a power user and don't want to fry the CPU.

2) Failing that I could try removing one of the fans (not sure which one would be better?) to see if the CPU temps remain acceptable and if I get suitable noise reduction.

3) If that doesn't work, is it feasible to try buying some quieter fans (like a quieter Silverstone or Noiseblocker-brand fan). I'm not technically inclined enough to know if these could be properly grafted on to the heatsink that came with the Havik, or how many fans would be required.

4) Maybe the most definitive option is to remove the Havik altogether and get a much quieter Noctua (or similar) cooler. I don't mind paying out another 100-150 at this stage, if necessary, although I just wish I'd been sensible enough to do that at the beginning! One thing I am worried about is that even though I tried to get relatively low-profile RAM, there is almost zero clearance (about 1mm or less) between the right-hand fan and one of the RAM modules. Reading reviews for the better cooling products suggests that this could be a problem with them too. The R4 is 230mm in width total.

Am I going about this in a reasonably sensible manner? Don't want to miss anything. I've included a photo.

First off: what temps are you seeing at idle and load? Let's make sure there isn't another issue.

Second:
I'd remove the rear-facing cpu fan. You'll get a little bit of pull effect from the rear case fan and you probably don't even need the 2nd CPU fan with your 77W TSP CPU. Then, go into your BIOS and see if you can enable the bios-level fan control for this 3-pin voltage controlled fan. See if that resolves the issue.

If it doesn't, and you can't get Fan Xpert to work, you could try Speedfan.

If that still doesn't cut it, you could get a different (PWM) fan.

For the temps, I tried using Prime95 to test. Screenshots are attached.

No noticeable change in noise when pushing to full load.

Assuming there's no issues with the temperatures i'll try removing the rear-facing fan, thanks!

Temps look fine

Perhaps the CPU fans aren't compatible because they are 3-pin fans. Try plugging them into 3-pin fan headers and see if they are controllable. And I would remove the rear facing fan in any situation. It's simply not necessary for cooling the 3570 non-OC'ed.

By way of update: I've taken the rear-most fan off the heatsink and run some CPU tests again. There is some noise reduction although it is still louder than I would like, so I might start looking at a new fan. I've posted the temperature charts from full load just for comparisons sake - I'm not seeing anything alarming compared to when there were two fans though.

I will give the other ideas mentioned about looking at the BIOS a go this weekend as well so as to see if the fan voltage can be adjusted.

There should be a setting in the BIOS for the fan to be voltage or PWM controlled...make sure it's set correctly for your 3-pin voltage controlled fan.