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My QS 933 has always been quiet.  In fact, I think that my B&W G3 was louder than this thing.  I can hear the HD access, and I must say that it is a pretty quite hard drive compared to what I have had in the past.  My PC's on the other hand are louder than all my mac's put together.  I can have a PC started up across the room from my Mac, and when I do I can no longer hear my QS fans or hard drive.  Shut it down, and all I hear is a quite hum from my QS.  Maybe I just got lucky? 

It has been a week since I performed the mod. What can I say, purfect!

I have been running backlight 2 with the Matrix GL saver constantly for a week now. This has kept the CPU activity well above 20% at all times. Even with this constant CPU load, the CPU fan hasn't kicked up to the faster speed. The only time I have had it kick up was during a few DVD re-codes. (I'm backing up my Anime stash B4 I go to Uni, there is no way I'm taking $200 worth of Anime DVDs)

I am still seeking quieter 12cm, 6cm and maybe even a new PSU. If anyone knows any good brands to try/lookout for I'll give them a whirl. I'm trying to make my QS silent.

Well originally I used a B&W side fan, that worked quite well. Today I went to the computer fair and picked up two fans that use ceramic bearings. One 120mm and one 60mm half height. The 120mm needed to have the plug from one of the Apple fans soldered on, but that went smoothly. The 60mm half size was a mistake, it appears to not put through enough air. If I start getting kernel panics I'll return it and get the full size one.

Still, I'm keeping the CPU activity above 50% and there hasn't been any glitches but the heatsink isn't as cool. It might need that full size 60mm for the CPU. The sound is amazing, there is almost none! Very low background noise, nice!

How much space do you have available for each?

The more space available, the more you can do... if space is available, mounting a larger fan on a suitable adapter would allow some combination of greater airflow/less noise- in your case, a low rpm, low noise 92x25mm fan on a 92->60mm adapter would allow the use of a very low speed, quiet fan that probably still moves more air than the original 60mm & avoids the 'dead zone' of near-nil airflow under the hub (usually also the hottest spot on the heatsink), giving near-silent operation without need to vary the speed. An 80->60 arrangement would also be an improvement.

I'm not familiar with the QS case, so I'm not versed in the exact requirements. This is the kind of adapter I mean, so you can probably tell at a glance if this approach is viable.

As a rule, larger fans are quieter for any given level of airflow. This includes depth as well as diameter, so I'm not surprised a 'half-size' (half-height?) fan is less desirable than the original.

Vibration-deadening gaskets are also available, like

http://www.svc.com/vafanvidakit1.html

Last edited by Bat (2005-02-06 4:53 am)

reece_james wrote:

...A clever mod would be to add a fan to the top of the heat-sink by grinding a hole, no idea how effective that would be...

I did this in my Mystic. I'm not sure how clever I'd consider it, tho.

It just required a Dremel, to cut away enough of the aluminum heatsink to squeeze the fan on ( or rather in, as I cut a square hole ).
I then placed the fan into the heatsink, to pull heat away more quickly from the overclocked processor.

I would also like to find more silent fans, to replace the stock fans.
There are much louder fans than what come with the Mystic, but there are also much more silent ones. I've actually entertained moving everything into a nicely designed aluminum ATX, with new fans and all ( and, ahhhhh, room for expansion ).

I wasn't suggesting adding fans, I was suggesting replacing the 6cm CPU fan with the larger fan/adapter combo if there's room. Normally that should just bolt or screw on, but as I say I don't have experience with that model, or something like a set of photos to help.

If that would work, you'd have all the cooling you need and near-silent operation- e.g., the most powerful 6cm fan I know is the 60x38 Delta EHE, rated 50.1cfm at 8000 rpm. Sounds like a dental drill... you should be able to approach that, even funneled thru an adapter, with a 92mm at under 2500 rpm, as low as 21 dbA.

If you can point me to a set of good photos, it'd help.

Unfortunately the clearances only allow for a 6cm fan. (It fits between the PSU and the motherboard.) Remember that fan I bought to replace he original fan? It shat a bearing about 5 minutes ago! Jeez. Oh well I'm back to the original Apple 'turbine' 6cm. I really need to got my hands on that ceramic 6cm now!

Yeah a bit of a bummer. This fan breaking didn't help either. (I'll take it back and ask for a refund)

Yes it is a 60x60x25mm fan. The half size ceramic one is 60x60x12.5 and it just doesn't have enough 'force' to push the air through the heatsink. (The CPU fan is mounted 90

That Sunon fan is the noisy blighter that Apple uses! That is the little bugger thats causing the problem!

reece_james wrote:

That Sunon fan is the noisy blighter that Apple uses! That is the little bugger thats causing the problem!

Interesting... you're sure that's the exact unit, product number matches? Sunon makes a lot of fans, even in the 60x25mm size.

I know some extremely quiet units, but they usually only move about 12cfm.

Too bad there's apparently no room for an elbow duct or hose (it's years since I've seen interior photos). Of course there are other ways of cooling, but things like watercooling are probably beyond your means.

Yep thats right. It bows air straight across the heatsink onto the back of the optical drive. I've given it a good test today, the CPU activity has been sat on 100% in 40