Thanks to you guys I managed to get a pretty quiet system, but the rear chassis fan (sendis air out) seems to be vibrating against the case making a small enough noise to annoy me.... or maybe the fan isn't quite smooth enough, causing it to make a pulsing sound.

My 120 mm CPU cooling fan + my GPU fan are quiet enough, but not the rear fan. I have a Cooler Master Elite 335 case. Are there any tricks to make the fan quieter i.e. securing it with something etc. or do I need a new fan?

Thanks

Try some silicone fan mounts, for example:
http://cgi.ebay.com.au/NEXUS-REAL-SOFT-SILICONE-FAN-MOUNTS-PKG-OF-4_W0QQitemZ250598089435QQcmdZViewItemQQptZLH_DefaultDomain_0?hash=item3a58cf62db

If you haven't done this already, (in addition to the rubber fan mounts suggested by alleycat) also try cutting out the rear fan grill - that fan grill looks pretty restrictive. This might reduce any whistling-type noise a bit.

The sound is like a fan ticking but 16x the speed sound but and lower of course a different sound. How would I determine if it's caused by the fan or the attachment to the case?

Thanks for the mount link. I'd rather avoid eBay, but everywhere else is $15 + shipping in Canada or $13 in store.

Detach the fan from the case and see if it still makes the noise?
Theseare pretty effective - I've used a couple of them in a Lian Li case. I don't know if they are available in Canada?

I agree with cutting out the restrictive rear vent. The grommets are pretty pricey, but come free with a Nexus 120mm fan.

Buy the quieter fan and get the grommets for free... or buy the grommets and get a quieter fan for free... There has to be someplace in Canada that sells the Nexus fans. MikeC is from Canada, maybe he knows.

What kind of CFM should I look for in a rear case fan?

So far I've found these:

Scythe Kama Flow 2 Extra Fluid Dynamic Bearing 120MM Case Fan 900RPM 11.0DBA 30.54CFM EX-FDB
Scythe S-FLEX SFF21D 120MM Cooling Fan 800RPM 8.7DBA 33.5CFM FDB
Scythe S-FLEX SFF21D 120MM Cooling Fan 800RPM 8.7DBA 33.5CFM FDB
Scythe Slip Stream Kaze Jyuni 120MM Fan 800RPM 40.1CFM 10.7DBA
Scythe Slip Stream Kaze Jyuni 120MM Fan 500RPM 24.5CFM 7.5DBA
Scythe Slip Stream PWM 120MM Sleeve Bearing Fan 200~1300RPM 0~26.5DBA 0~74.25CFM 4PIN Adapter

Here's NCIX's list of fans:
http://www.ncix.com/products/index.php?minorcatid=1164

I know Nexus are said to be among the best, but the only options are between one with LEDs, which I don't want and a Nexus 120MM Real Silent Case Fan BLACK/WHITE 1000RPM 22.8DBA 36.87CFM 3/4PIN.

Newegg Canada carries it:
http://www.newegg.ca/Product/Product.as ... 6835610006

As does NCIX
http://www.ncix.com/products/?sku=17808

NCIX also carries just the silicone fan grommets for $5 CAD.

Edit: NCIX also carries the Yate Loon D12-SL12 which I do believe is the same fan as the Nexus. If I am not mistaken the fan is actually made by YL and rebranded by Nexus. Reviews of the Nexus and Yate Loon fans on the main SPCR site answer these questions with the Nexus offering different color options and adding the grommets.

Should I get a fan controller or is running at the default speed fine?

If you have a case resonance (aka cavity resonance) then you can alter this by reducing the constriction of the intake, too.

If your motherboard has a fan header, use it. Otherwise plugging it in to one of your 4 pin Molex connectors will work fine. At it's highest speed it will be barely audible in a reasonably quiet (suburban apartment, no traffic, fridge off) room less than a foot away.

If it's too loud at that point then yes, get a controller, and a hearing test.