[vdr] Re: cpu cooling

["Sven Karlsson" <svenka@it.kth.se>]

Hi all,

Earlier this year I did build an almost fanless machine. I suggest you have
a look at the Via C3 processor. It is slow but I can watch DVDs and Divx:es
on my 933MHz C3 without problems on it. I do not have any DVB card in that
machine though.

Here are some specs:

* Via C3 933 MHz
* Via 694 based motherboard (AFAIK only Via does chipsets that work properly
with the C3)
* one 40GB Seagate Barracuda IV in a SilentDrive enclosure
* 256 MByte standard PC133 sdram
* standard fanless off-the-mill geforce2 MX. You can probably use a MX440
too. The geforce has good support for TV-out and that's why I use it.
* standard creative soundcard
* Nec 5700B DVD player

Now for the fun part, i.e., the cooling:

The CPU has one Zalman CNPS6000-Cu (there are neven newer models available)
without fan which is supposed to be "hanging in the air" above the heatsink.
I do not use that fan, only the heatsink. I use artic silver III as thermal
paste.

The case is a standard chieftec one that is rebranded as a thermaltake case.
It is quite good a roomy with lots of space.

The case is ventilated (next to the CPU) with a single Papst 8412 which is
powered by 5V (it is normally at 12V) and this thus both slower and less
noisy.

The PSU is a special low noise one from Q Technology. I think SilentPC in
Netherlands have these. The fan in that one has been replaced by a Papst
8412. The voltage on that fan very rarely goes above 7-8V!

There are fans that are even more silent than the papst but I haven't tried
them.

If anyone know of any good completely fanless ATX PSU I'm more than
interested! The only thing that is even remotely noisy on my box is the PSU
fan. The entire box is much less noisy than my Philips VCR and par with my
old Technics CD player (more than 11 years old now).

The key to all this is really the C3. It only need 9W of power which makes
it very easy to implement a good cooling system. I think the most power
hungry part (and thermally hot) by far in my box is the geforce card.

The CPU goes up to 49 degrees C and stays there no matter what so I think I
even could remove the case fan but I cannot really hear it oven the PSU fan.
This will change I hope if I could get a passive PSU.

I hope this helps. The CPU isn't very fast but as I said: it is fast enough
for realtime divx over the geforce so I'm happy with it!

I'd gladly answer any further questions you might have...

Best regards
 Sven