For my next build I've been looking around at cases, and this one caught my eye.

http://www.lian-li.com/v2/en/product/pr ... s_index=62

I like the following features about it: the HDD cage is rotatable; the ports and buttons are on top; the basic simple design; it's a medium (ie. not too big, bot too small) ATX case; that there are only two vents; and finally, the fact it comes in silver (I have a weakness for silver cases). Of course I'd probably swap out the fans(s) for quieter ones without silly led lights.

Sources of potential noise would obviously be the front vent. I'll be using a 120 GB capacity SSD plus a 1 TB HDD, so although the front vent air flow would help with cooling the interior in general, it's probably not that crucial for my storage drives at least.
I'm thinking of going with an i7 Ivy Bridge 3770 and either onboard GPU or a low power card. I don't game, but will run CS6.

My question is: If I choose quiet components, will this case be able to keep things at around 20 db or less? Anything I should be aware of with this case? Potential vibration maybe?

Broadly speaking it's an aluminium Lian-Li: check the latest SPCR reviews (K59, B25), which let you make some reasonably educated guess.

More probably than not, you may expect some hum, hard drive vibrations, not quite good fans, maybe some quirky build issues.

More probably than not it can be done (at least with the IGP), but maybe with not such a great value, money&cooling&noise wise.

I've built two very quiet systems using a A-05B and a Lancool K7 cases. I'm about to put together a Ivy Bridge system that's going into a PC-6 case.

Since I don't game, I don't need a high powered graphics card. I do have 4670 passively cooled cards in the existing systems and the new one will use onboard graphics (an add in card won't help Lightroom, which is the primary use of the box). I generally don't like the way Lian Li manages the air flow in their cases. For cases like the PC-7 & 6, which are very similar, I would take out the front fan and only use the rear one and then tape over all the other openings on the rear panel and the vented slot covers. This way cool air comes into the case at the bottom of the front, passes over the drives, rises over the MB and exhausted at the top rear of the case. The air flow follows the natural convection currents in the case. If the openings in the rear aren't blocked, the air will be sucked in through them and "short circuit" straight to the exhaust fan and not contribute to the cooling.

As far as aluminum being a poor material for quiet computers, uh yeah. The primary factor is the execution of the build details. The only issue I've had with cases contributing to noise are resonances of large panels (typically side panels). The simplest solution is to get some window/flashing membrane from a place like Lowes or Home Depot (http://www.homedepot.com/h_d1/N-5yc1v/R ... reId=10051). It's a very sticky rubbery plastic that a couple of mm thick. It changes the Q of the panel and works great.

If you blocked all rear slot holes, would you still need to remove the front intake fan? I would think the front fan would help direct the airflow better than a passive opening.

I don't have an hands on experience on those Lian-Li as b_rubenstein, but usually a front intake is the more straight path to the ears: in my experience, even with well damped cases like the Antec Solo, it wouldn't worth to have a fan running through it, noise-wise, unless you have some heat source right behind there to cool (which cannot be cooled elsehow).

A fan really doesn't "blow"/direct air inside a case; it creates a high pressure area in the case The air flows from a high pressure area to a low pressure area. To a certain extent, an exhaust fan is something like pulling a rope, which is easier than pushing it. A fan can be used to force more air flow into an area such as a CPU/GPU cooler.

Is it more efficient to have one rear exhaust fan pulling air out than to have both a rear fan pulling and a front intake fan pushing?

AFAIK there isn't a general answer. And first of all you have to define that "efficiency".