Going fanless or low speed conventional...

[Avig70]

Hello all,
I need/want a very very quiet PC, ultimately I would want to go compleatly fanless but like everything in life there is a negative aspect to everything we do. Fortunately my computing requirements are not that demanding. Usually a Windows OS, with the occasional anti virus program, I watch allot of HD movies, my 2 YO son plays his silly games on it and uTorrent client is always in the background, so OC is not needed. Given that, I think a good i3 (3220...) with 8-16GB memory would suffice. I initially thought to go compleatly fanless so I bought the SeaSonic X-460 fanless PSU and had my eye on the NoFan CPU cooler and CS-60 case. After that I decided to read about actually building a quite PC and I understood it's a bit more then buying a fanless PSU, fanless CPU cooler, an SSD and to put it all together. My conclusion from all the reading is that only a curtain part of the system is fanless but you need some kind of airflow inside the case to use these "fanless" products and I haven't even considered the cooling of the motherboard... That's a shame cause were I'm from there's allot of dust and going with a fan solution means I'll keep cleaning the insides of my PC once a month

So, I already have the SeaSonic fanless PSU, I have an OCZ Vertex 3 120GB SSD, Arctic silver 5, how do I go about designing the airflow in the case when I want to go compleatly fanless? Is somekind of fan really necessary?
Thank you for reading this far

[CA_Steve]

Hi and welcome to SPCR. There are two ways to go:
- fanless. Here's a case for that. Pricey, but it works.
- fanned, but pretty darn quiet in a conventional case.

As for dust collection, you can reduce that by having positive pressure in the case - that is, just have more fan cfm going in than out ( 2 input fans and 1 output, 1 input fan at higher rpm than the 1 output fan, etc..).

Consider the i3-3225 for a few $'s more than the i3-3220. Same speed, but has the HD4000 iGP instead of the lesser HD2500.

[Avig70]

Dear Steve,
Thank you for that 3225 Vs 3220 differentiation, I will most certainly go for the 3225 instead. Mistakenly for some reason I assumed the on board graphics was a part of the chipset and not the CPU.

As for the case, I see it needs Pico PSU and it can't take the fanless seasonic I own.

For a case I saw on another thread a recommendation for Fractal Design Arc Mini, it has a bottom fitted PSU, allot of mesh that might suffice for fanless and room to route the cables beneath the motherboard so I'm looking for good cases with the potential to be fanless if possible and all without breaking the bank.

Do you guys think I can get away with Noctua HN-14 or ThermalRight Silver Arrow with only one slow spining CPU fan, with the whole cooler mounted 90 degrees to one side so it would create the bottom to top air movement needed?

As for the dust problem, even if you have positive pressure you're still doing it with air full of dust, I don't see any other way to do this other then to filter the air going into the case, am I missing something?

[CA_Steve]

The fractal case is nice. With positive pressure, most/all of the air going into the case is via the input fans that should all have filters. So, the filter should help alleviate duct build up inside the case. With negative pressure, air can enter from any gap and is not filtered.

Honestly, a slow moving case fan in a low resistance case is inaudible.

[kuzzia]

Besides one or two intake fans you could also add a slow spinning fan on the CPU cooler. The fan supplied with the Scythe Mugen 3 only spins at 300 rpm at its lowest speed. You'd be hard-pressed to sense such a low noise level.

[tim851]

With what you describe I'd say buy one of the Sandy Bridge Dual-Core Celerons and 4 GB RAM. You don't need any horsepower as it seems, so you'd just be wasting money buying an i3. Put a Thermalright HR-02 on it, vertical orientation, and you're good.