[Pob255]

Part 3

Fan testing and the hunt for noise. (by hand and ear)

First thing to mention here is Beware of fast spinning fan blade and your fingures. I have gained a few cuts in my hunt for trouble fans.
A premptive fabric plaster on a fingure tip can be very handy.

You can safely plug and unplug fans into your pc while it's on (although molex connectors can be very stiff and a right bugger to do) also a 3pin extention cable can be very useful here as it makes it eaiser than trying to reach the motherboard around card and cables.

To test Fans on a molex connector only a good trick is to use a spare PSU or remove your current one and jump start it ( All it requires is a paperclip ) then you can connect your fans to the molex connectors while it's out of the case and easy to get to +the only other fan running is the one on the PSU (I still have an old Qtec psu which is used to test molex fans)

The measure fan speed the eaiest way is to have a monitoring program running (eg speedfan or even just go into the BIOS it'll be under "PC Health Status") and plug the 3 pin connector into your motherboard and see what it reads the fan speed as. (although these numbers sometimes lie)
You can gain a rough idea as to how much sound and air is moved if a fan is slowed by very carefully putting your fingure onto the top of the central "hub" and pressing down slightly useing the friction so slow the fan, don't worry if you stop the fan it will not damage it, unless you use so much force you physically break something, but you should stop the fan long before reaching that much force. (a sticky plaster on the fingure can also come in handy here to protect you from a friction burn)
Remember that your fingure tip rubbing over the fan hub is makeing sound, but lissen carefully, it'll be a differnt pitch, your lissening to the fan noise.
Keep an eye on your monitoring program to see how much you are slowing the fan by. 50% of it's normal speed in generally as much as a fan controller can do.

To test vibration, you seem to have gotten off to a good start here, feel the side panels and case around each fan to try to work out whic are the worst offenders (note one bad fan can cause the while thing to vibrate) then unpulg fans or unplug all but one and work your way through them untill you find the bad one/ones.

Remove a fan from the case and simply hold it by the frame will also give you a good feel for the vibration and howmuch the sound will be reduced by if you use vibration damping on it.

To test a grill/mesh remove the fan and see how loud it is the hold it up to the grill/mesh and see how much it effects it.

Be methodical work through each fan in turn, good chance you'll have to take all the fans out of the case to give them a thougher testing.

What you can do about the sound?

Anti-vibration:
well you can buy rubber plugs to replace the screws http://www.scan.co.uk/Product.aspx?WebProductId=487037 but at £4.60 a fan it's a bit pricey

I seem to remember someone here uses whitetac to hold his fans in (it's like bluetac but slightly softer) I've never been to sure about that, I'd worry about my fans falling off.

What I use is hair bands like this http://shopping.erol.co.uk/product/D...-18-Large.html get them from your local chemist or supermarket, the ones with out the metal joiners for prefrence but it dosen't matter much.

Now what you do is cut the in half at the join to make one long length, you can seal the ends with a cigarette lighter, feed it through two of the screwholes of the fan vent, so you have two equal lengths of elastic sticking into the case then do the same with a 2nd hair band for the other two screwholes, now attach your fan by feeding the elastic ends through the screwholes in the fan frame. pull the ends of the elastic tight, then pull on the fan slightly untill you have about 1mm clearence between the fan and the case (you can tie knots in the ends of the elastic but I find the friction holds it in without problems.) Vola one suspended fan for the grand total of about 30p

2nd methord is basically the same but cut each hairband into 2 lengths tie a knot in one end then feed it through the case, so instead of two double ended lengths you have 4 single lengths.
You may need some washers to help secure it as you may find the knot will pull through the screwholes.
Any DIY/hardware store will have washers and they are dirt cheap, just make sure the holes in the washers are smaller than the screwholes in the case, rubber washers would be best here.

Rubber/Silicon Washer or Grommets, the idea here is simple get some rubber/silicon washers (rubber will be black and silicon clear both are a soft materal) now put one on each side of the screwholes of the case before screwing in the fan, the idea here is the both the fan and screw head are held off the case by the washer alowing it to absorb the vibration.
A grommet is basically a double sided washer the fits in the hole it's better than washers as the sides of the screw are also surrounded by rubber as it passes through the case, the down side is the hole need to be larger than the screw so you'd have to enlarge the holes in the case.
The down side to these is that while they reduce the vibration they don't do it as much as a rubber plug or the hair band methord. and they are rather limited with high levels of vibration.

Slowing down the fans.
Depending on the current fan speed just slowing them down can help alot.

For 3pin connectors
Sotfware, you can sometimes use software (speenfan can be setup to slow fans, but it depends on your motherboard compatibility with it to if you can or not) sometimes you can also do it in the BIOS (however from you pic's a see you have a ECS motherboard, I seem to remember they mainly make cheap motherboards so it's doubt full if it has this added feature)
Software can be very hit and miss in my experience.

Fan controller, a very easy way to control the speed of multiple fans, they do range from cheapish to expensive. also have the advantage of alowing you to use more 3pin fans than your mother board has connectors for.
I myself use one of these zalman fan controllers http://www.scan.co.uk/Product.aspx?WebProductId=683697 for £19 it lets you control upto six 3pin fans, it's very easy to fit. It's manual control only so you have to fiddle with the knobs to adjust the speeds, you can also put you cpu fan onto this as well as case fans but I prefur to let my motherboard automatically adjust the cpu fan speed so don't have to worry about it.
You can go up quite a bit in price to something like this http://www.scan.co.uk/Product.aspx?WebProductId=517726
Which you stick inside your case and it adjusts the speeds automatically based on temptures via 4 probes you can wire up to areas of your case.
however I'm guessing £50 is out of your budget.

Resistor extentions
you can get short 3pin extension cables with a resistor on it to slow a fan http://www.acousticpc.com/zalman_3pi...or_56_ohm.html
Dwon side to these is they are not easy to find and you are limited by the number of fan connectors on your motherboard.

For 4 pin molex connectors.
you cannot directly use a fan controler or simular but there is a simple mod you can do to slow down the fans
7v and 5v fan mod, basically fan run off 12volts supplied by the 12v pin of the molex connector
(the yellow wire is +12v, the red is +5v and the 2 black wires are earth btw)
Now what you do here is remove the pins from the molex connector of the fan and swap them around.
simple pin removal tool
To reduce the fan to 5v you swap the red and yellow pins over.
To reduce to 7v you swap the black pin the fan is connected to with the red pin.
Here's a guide http://www.techpowerup.com/articles/other/137
There are hidden down sides to this.
5v, not all fans will be able to run at 5v as it can be just too little voltage for them to start or keep running. (side note, this is why most fan controllers have a bottom limit of 6v)
7v, you get this by feeding the 5v back down the 12v line to generate resistance, which is not always that healthy for the PSU. While you have been very sensible and not skimped on the PSU and got a high quality corsair HX520w so it should be able to cope and not cause any major damage you do run the risk of shortening it's lifespan.


Better Fans
This is probably a good option, although I'd test all the current ones first before splashing out on replaceing the lot. esp as it might only be one or two causeing issuse.
High quality fan are very nice, (I've not used a nocturn fan but I do love the Scythe S-FLEX fans) however they are expensive £12-15 (esp if you need to get 4 or 5 fans) and you can get very good resaults from fans that cost half the price £6-7

Some basic things to remember, the faster the louder, the slower the less air flow.
This is a basic rule that applies to ALL fan reguardless of blade shape and number, although that said blade shape and number does have and inpact of air flow and volume.
Other things that effect the performance are production quality and bearing type (I mentioned the two main type but there are others and veriations in all types)

Couple of rules of thumb,
1000rpm and below = very quiet but not much air flow.
1200-1400rpm = quiet but reasonable air flow.
1600-2000rpm = bit louder but good air flow
2200rpm and above = massive air flow but does make you case sound like a vacume cleaner.
Don't trust the numbers, take them with a pinch of salt. there is no fixed standard here and numbers are often twisted. use them as a rough guide the othe good rough guide is the price, if it's £2.50 it's not going to be any good.

Fan's I've used
mid price, very quite fan, not great air flow http://www.scan.co.uk/Product.aspx?WebProductId=615592
mid price, good well ballenced between air flow and sound http://www.scan.co.uk/Product.aspx?WebProductId=590760
both of these fans are very good for the under £6 low cost, I'm quite a fan of the Sharkoon System fans just don't go for the power one, yes it moves a heck of a lot of air but it's very loud. (it is both the loudest and most powerful fan I've used)

If the top 140mm fans are giveing you trouble I seriously consider the 140mm Sharkoon system fans

The Sharkoon Golfballs used to be very highly recomended on these forums, the 1000rpm ones are very quite but not a great air flow, the 2000rpm ones are a good balanced fan (the air flow and sound are below what I'd expect from a 200rpm fan) both around £7

If you want to splash out on a S-FLEX or Noctua, then don't go for the 800rpm ones, they are next to slient as possible but don't move much air. the 1200rpm or 1600 rpm are much better and still very quiet. and cost around £12-13