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micha schraven · Apr 20, 2001, 04:00 AM

Hi, my old BondiBlue 233 mhz rev B, with 30 Gig/96mb is now used as a server. During night, I am having trouble falling asleep with that noise coming out of the machine.

Anyone knows a good fan that does not produce much "HMMMMMMMMMM" ?
at work I use a HP e-vectra which is virtually silent.

Apr 20, 2001, 05:13 AM

accumulated foreign debri is causing rotor rotation imbalance, hence the elevated acoustical disturbance (noise). careful cleaning (so as to not overstress the bearing(s)'s designed radial and axial thrust limitations will resolve the problem.

itomato · Apr 21, 2001, 03:51 AM

Electric motors work best when the bearings that support the moving spindle are lubricated properly.

If you follow his ^ advice, make sure you re-lube the fan. I has resuccitated several PC cooling fans by soaking them in rubbing alcohol.

They work fine afterwards, but if you're going to go through the trouble to take it apart to access the fan, you might as well replace it. They come in standard sizes, and your local Radio Shack or Computer store would likely have an exact replacement.

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waffffffle · Apr 22, 2001, 11:27 PM

My sister leaves her iMac on all night and she has gotten used to the noise. I used to for her to leave it on because I was using IP Net Router through her internal modem, and later on through a cable modem. I'm at school now, and the network is now routed through the Linksys 4-port router so she has no reason to leave her machine on anymore but she does. The original iMac is definitely a noisy machine. Apple obviously noticed. I'm sure my sister would appreciate any info on reducing the noise, even though she's gotten used to it.

kokosnootje · Apr 25, 2001, 12:08 PM

Mischa,

I just replaced the fan of my rev b iMac and are having a couple of weird problems. I replaced the original fan with a standard 12v 80x80mm pc fan.
The fan did not turn. I thought I had done something wrong. I found out that the fan is not driven with 12 volts. The replacement fan wil work on the lower voltage but it has problems starting.
The second problem I found once I got the fan going is that as soon as the fan starts to turn, the picture on screen starts to wobble from left to right, it becomes shaky.

I think that the second problem stemms from the fan creating more of a magnetic field, compbined with the fact that it is situated very close to the picture tube.

I'll try to shield the fan a little better and will let you know.

Groetjes,

Kokosnootje

Apeldoorn,
The Netherlands

micha schraven · May 7, 2001, 09:07 AM

bedankt, but I remember a guy who just broke the fan out of the imac and replaced nothing. the temperature change was only about 15 degrees. The iMac was silent after this amputation.

If I make a few holes in the case, maybe, it improves cooling.I have got a 30 Gig 7200 rpm drive in it, which may make my iMac hotter than that guy's standard iMac.

waffffffle · May 30, 2001, 01:34 PM

I know it's been a while but has anyone had any luck with quieting this machine? I'm home now and I hooked a stereo up to my sister's iMac because I thought the sound was horrible out of the internal speakers. Now I know it's because the machine is so loud. Is removing the fan safe? What's the worst that can happen? The room is usually very cool and it's not like the computer is kept on a carpeted floor like towers usually are. Any info? Thanks.

smic · May 31, 2001, 12:38 AM

ill try that out too
in the next couple of days
sounds like an awsome idea, but i have an extra heat sink fan from an old 486 and some thermal compound, so ill add those in instead of the other fan
be almost whisper silent then i hope

kokosnootje · May 31, 2001, 05:43 AM

I tried without the fan. My Rev/B would warm up within 30 minutes to about 79 degrees centigrade. I have not been brave enough to see how long it would take for the processor to meltdown.
The metal panel in which the fan is mounted has a gray sticker covering up holes in it. you could trie without the sticker to see if the air circulation will improve.

smic · Jun 2, 2001, 01:11 PM

well i couldnt get the other fan to stay on top of the heatsink
so i went fanless
BAD
in a couple of minutes of quicktime movies and startin up unreal it was at 79 degrees Celcius
way to hot considering i usually am sitting at 40 at the max after playin quakeIII
so without the fan is not good, but it was nice havin a silent iMac for 10 minutes
ill try to find a quieter fan to fit in it and see what that does

Feathers · Jun 3, 2001, 09:09 PM

The noise is coming from two sources, the Fan AND the HD. I notice you've bitched up the HD. The new one wouldn't be a Maxtor by any chance would it? There is the HUMM caused by the Hard-Drive, you know it's the HD if you place your hands on the casing and it almost goes away! That can be minimised by using nylon screws instead of metal to mount the HD and move it around to minimise HD contact with the chassis. You can also try and stop the case from vibrating by making sure all the screws and clips are tight, you can even lodge bits of paper in the gaps!!!! A muffler that absorbs the vibration of the case without blocking the air circulation WILL make an appreciable difference, maybe just enough to send you off to sleep!

The WHIRR (as opposed to humm) of the Fan is REAL annoying though. I found that when I put my Bondi-Blue on a tilt and swivel base, overall it sounded noisier but the speakers also sounded louder too! The greatest noise producer was (and is) the HD, though.

Jun 4, 2001, 04:33 PM

my login dont work
but anyways the harddrive in my imac without the fan wasnt that noisy
its the fan, somehow, im going to see if i can find a fan to fit that is quieter

itomato · Jun 4, 2001, 09:17 PM

http://www.quietpc.com/casefans.html

These are super-silent, supposedly. I've got no experience with them, personally, but a lot of people do. They also make a special noise-reducing hard drive enclosure that may or may not meet the space constraints of the iMac..

iPad · Jun 5, 2001, 01:37 AM

I'd personally go with an 80mm Panflo, they're somewhat quiet, but you get REALLY nice airflow rates. I'm gonna do a fan mod to my Yosemite G3 next week...add a **** load of fans, then i'm gonna try 450 from 300 (it's already at 400), i've also got a globalwin FOP32-i, so i'm going to TRY to get on my CPU, first thing, gotta remove the zip drive and put in my PC.