Does anyone else's Mac Pro resonate?

[Spanky Deluxe]

At first I thought I was going mad but this noise is definitely there.

My Mac Pro is pretty much silent, I can't hear the fans and the only real noise that I can make out above anything else are the hard drives making a racket when I use them. My room doesn't have much background noise at all and in the early hours of the morning it is completely silent.

Now I can definitely hear this resonating noise that sounds for 5 seconds then fades away so has a total period of about 10 seconds in the form of a sine wave. Its irritating the hell out of me! Its not very loud, i.e. much quieter than the hard drives but is really noticeable when I'm trying to read through a physics paper in silence and its really distracting. I'm guessing two of the fans must be causing this resonance but before investigating it further I thought I'd ask anyone else if they can hear this.

Spanky

 

[knome]

thats crazy, the only thing that might be causing it is if the fan aren't secured properly. Try opening the case and see if you can wiggle the fans around.

 

[suneohair]

X1900 maybe?

 

[technicolor]

Mine does this too. I thought it was the HD. But yes it is annoying as all get out.

 

[Mundy]

My Mac Pro was doing this whenever a CD or DVD was in the optical drive. I figured out that there was too much of a gap between the aluminum riser the optical drive sits in and the case itself, so I folded two small pieces of paper and slid them underneath the riser, creating a tighter fit. The resonation is gone now.

 

[suneohair]

My Mac Pro was doing this whenever a CD or DVD was in the optical drive. I figured out that there was too much of a gap between the aluminum riser the optical drive sits in and the case itself, so I folded two small pieces of paper and slid them underneath the riser, creating a tighter fit. The resonation is gone now.

Yea my optical is very very noisy. I may have to get some sound proofing material for my Mac Pro.

 

[zakatov]

it could be beats: it's an effect that happens when two sound sources produce very close (but not identical) in frequency sounds. In your case (haha, pun), two fans are responsible for this. The beats occur when the two sound sources constructively and then destructively interfere with each other, producing a beat in a form of a sin wave.

 

[Spanky Deluxe]

it could be beats: it's an effect that happens when two sound sources produce very close (but not identical) in frequency sounds. In your case (haha, pun), two fans are responsible for this. The beats occur when the two sound sources constructively and then destructively interfere with each other, producing a beat in a form of a sin wave.

Yeah that's what I thought it was but I can't think of any way to shut it up. I've never had a computer this quiet before so have never experienced this kind of thing. Even my mini was noisier.

 

[NATO]

Lift the latch at the back of your Mac Pro, I found that essentially killed the resonance.

 

[Puzz]

I had similar growing/fading resonance.

Tightening the screws on the drives in their carriers fixed it for me.

(Actually I replaced the cute aluminum round ones with normal mounting screws, since the cute ones were stripping out pretty fast.)

 

[ljones]

No such thing here, loud DVD Drive as I've mentioned countless times. Other than that, very quiet.

 

[knome]

No such thing here, loud DVD Drive as I've mentioned countless times. Other than that, very quiet.

well i don't think its going to help if your drive is not encased in plastic or dampened by the actual tower case, seeing as how the front has holes all over it. LOL.

 

[apoartar]

I don't have a Mac Pro yet, but plan on getting one soon.

However, I did once have a very quite PC laptop and every time I would do a large spreadsheet calculation I could actually here the memory or CPU making a very high-pitched noise. At first I thought I was hearing things but upon further testing, every time I hit "recalc", I would hear something like a very high pitched but very quite "YEEEEEEEEEEEEEEEEEEEE" and then it would quickly stop when the recalc was finished a second or two later.

That's probably not the noise you're hearing but it was pretty amazing to me that the CPU/Memory can actually make noise during heavy use.

 

[alien2108]

I have found out that in my Macpro HDD (Samsung 400Mb/16Mb cache) is responsible for resonances. You can clearly feel it vibrates much more that stock WD in MP. I even exchanged it for new one, but same thing. Releasing the latch at back eases the problem a bit. Bit it is still very annoying sinusoid sound. I tightened the srews, tried to use some rubber washers....Nothing helpes....

 

[ljones]

well i don't think its going to help if your drive is not encased in plastic or dampened by the actual tower case, seeing as how the front has holes all over it. LOL.

Well this is a abnormal loud. My other superdrive in my G4 isn't this loud with the side panel down and the front clip off. So it's louder than normal. Good thing i don;t use it to watch movies, or at all for the most part.

 

[Simon R.]

Yes, it indeed resonates. It is the casing and/or the harddrive bays and other metal inside. It gets worse when you add a lot of harddrives. Mine didnt have much of a problem with one disk, but with four it is rather evident. I am trying to get rid of it by placing foam pads under the "feet" and also making it "lean" against foam pads attached to a piece of furniture. So mostly, it is gone, but sometimes it comes back and I have to move around the Mac to make it stop.

Also, fiddling around with the DVI connectors and power cord, can change this resonating behaviour. Its a pity they didnt make some rubber coating inside to take care of this, since it can be rather annoying.

I think ,maybe placing some small pieces of rubber between the harddrive bays and the metal frame above, will help the problem. Have yet to try it out though.

 

[Harbl]

Sound/vibration dampening grommets can do wonders at reducing resonance. Radio Shack sells regular vinyl ones cheaply but silicone grommets will probably work better and last longer. There are also companies that make elastomeric mounting hardware for hard drives.

http://www.earsc.com/hddtechniques.asp

This place sells some other HDD "silencing" products. The Scythe HD Stabilizer works great for mounting a 3.5" in the optical bay. Newegg probably also carries similar products.

http://www.frozencpu.com/cat/l2/g7/c113/list/p1/Sound_Dampening-HDD_Silencers.html

 

[rsvrmille]

Relieved!

At first I thought it was just me, but I also have this noise. I thought it was the fans but it has only surfaced since i replaced the oem drive and put 4x400 16mb samsung drives in the case. It just hums away like a sine wave. Drives me mad! If anyone finds a way to get rid of this please post it. I'll try the latch trick etc tonight, if its like that with 1 400mb drive imagine what mine is like with 4 of them in! Is it a apple design problem or is it actually the drives?

 

[rsvrmille]

oops

forgot to mention, its a 4 drive raid array which problem makes it worse as all 4 drives are spinning...

 

[macrobat]

I had the same problem before I thought it was my x1900xt making the noise five seconds on then fade away I was going to post it but then I took a closer look and found it was my HD all I had to to was tighten the screws and push it a little and that was it sound stopped.

 

[IlluminatedSage]

Sound/vibration dampening grommets can do wonders at reducing resonance. Radio Shack sells regular vinyl ones cheaply but silicone grommets will probably work better and last longer. There are also companies that make elastomeric mounting hardware for hard drives.

http://www.earsc.com/hddtechniques.asp

This place sells some other HDD "silencing" products. The Scythe HD Stabilizer works great for mounting a 3.5" in the optical bay. Newegg probably also carries similar products.

http://www.frozencpu.com/cat/l2/g7/c113/list/p1/Sound_Dampening-HDD_Silencers.html

Harbi, thanks for pointing this link out. I am considering buying the Mac Pro soon, waiting for Quad Core CPU's to come out in Nov. so... hope your silenceing product would help. if i get annoyed

 

[peas]

as mentioned, it's the hard drives.
open up the case, and while the computer is on, apply slight pressure to the exposed surface of the hd, and you'll notice the sound is gone.

some silicon will fix this

 

[alien2108]

rsvrmille:

I think Samsung 400Gb drives (HD401LJ) are somehow really vibrating a lot. They are very quiet when head operation occurs (specially compared to Maxtor...) but vibration is just too much for MacPro case to handle...Maybe it troubles them since they are turned upside-down...Don't know...Like I said I already changed one and same thing with new one, so I guess it's normal for them.

 

[rsvrmille]

please god no

i can't put up with the humming, i love my 400LJ drives but its def them causing the problem. why did apple mount them upside down? its a little quieter when the mac pro gets turned upside down (to make the drives the right way up). i bought these drives specifically because spinpoint drives have always been really quiet for me in the past. Any other suggestions for a decent high capacity low noise drive if I have to RMA these?

 

[rsvrmille]

peas

hi peas, when you say some silicon will fix, can you elaborate? do you mean HD grommets?