We all know how metal cases can cause vibration noises to osudn loud
This could be solved by using plastic casing right? Are there any plastic cases otu at the moment?
I have a Sonata 2 - without the side cover on its fairly quiet but when the side cover is on it makes loud humming osunds - any ideas?
Plastic Cases?
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I'm not sure you'll find many plastic cases due to EMI (electromagnetic interference). I believe it would technically be illegal to operate a computer in an unshielded state (due to FCC regulations), and it takes something conductive (metal) to shield.
I did make an acrylic cube case for a mini-itx sized socket 370 mobo i got in 1999 or 2000 and it was a cool little comp. But, like i said, probably technically illegal.
I did make an acrylic cube case for a mini-itx sized socket 370 mobo i got in 1999 or 2000 and it was a cool little comp. But, like i said, probably technically illegal.
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Bluefront
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Being technically illegal, and actually causing any problems are two different things. You've seen clear plastic cases being sold openly......technically illegal but fairly harmless. Wood cases dangerous.....hope not. At least if your wood case burns, the fumes aren't nearly as toxic as burning plastic. 
If your metal case side rattles or humms, there are cures. First thing to do....find the thing that causing the problem, which usually is a solidly mounted hard drive. Temporarily set it on a piece of foam to see if the problem is solved.
If your metal case side rattles or humms, there are cures. First thing to do....find the thing that causing the problem, which usually is a solidly mounted hard drive. Temporarily set it on a piece of foam to see if the problem is solved.
Drive a car with excessive plastic parts (read: Saturn, Kia, Hyundai, etc) and tell me that plastic makes less noise than metal.
Plastic, if mounted improperly, will make just a much (if not more) noise than metal parts. It's less dense, meaning it will vibrate more and at a higher frequency at a given inductive energy.
What does work is isolating "like" surfaces. Using smooth plasic bushings or wedges in between metal parts (foam is better) stops 70% of most vibrations. If you have plastic parts, foam is really the only thing that will help there. Dampening will remove the other 30% of residual vibrations and noise.
EMI can be a problem if you have cheap components. However most computer electronics (mobos, CPU, mem, vid cards, etc) are usually rated to not exceed a certain EM emission level as a consumer device. But, if you buy cheaply made component EM leakage will be a big problem. It will unlikely cause personal health issues, but it can mess up everything from radio frequency reception (including phones, cordless mice/keyboards, etc) and in the other direction, having the potential for data corruption by absorbing EMI from external sources like microwaves.
The density and strength of steel and aluminum along with their machinability make them ideal for computer cases, with the benefit of some EMI protection. As a benefit to us, they are only moderately difficult to dampen...
Plastic, if mounted improperly, will make just a much (if not more) noise than metal parts. It's less dense, meaning it will vibrate more and at a higher frequency at a given inductive energy.
What does work is isolating "like" surfaces. Using smooth plasic bushings or wedges in between metal parts (foam is better) stops 70% of most vibrations. If you have plastic parts, foam is really the only thing that will help there. Dampening will remove the other 30% of residual vibrations and noise.
EMI can be a problem if you have cheap components. However most computer electronics (mobos, CPU, mem, vid cards, etc) are usually rated to not exceed a certain EM emission level as a consumer device. But, if you buy cheaply made component EM leakage will be a big problem. It will unlikely cause personal health issues, but it can mess up everything from radio frequency reception (including phones, cordless mice/keyboards, etc) and in the other direction, having the potential for data corruption by absorbing EMI from external sources like microwaves.
The density and strength of steel and aluminum along with their machinability make them ideal for computer cases, with the benefit of some EMI protection. As a benefit to us, they are only moderately difficult to dampen...
I have not done any tests but I'd think a thin layer of sheet metal,even basic window screen or aluminum foil-if grounded can make a wood or plastic "sandwich" structure have good EMI screening.
I've thought out a few odd DIY wood cases where the main panels would have a layer of steel or aluminum screen,grounded,and an inner layer of indoor outdoor carpet or Backpacker pad closed cell foam. Use construction adhesive(plenty) to bond it all and it could be pretty effective.
I have a roll of stainless steel sheet metal so thin it can be cut with heavy scissors. I'm gonna be careful what I use it for-since it's stuff you can't usually find.
I've thought out a few odd DIY wood cases where the main panels would have a layer of steel or aluminum screen,grounded,and an inner layer of indoor outdoor carpet or Backpacker pad closed cell foam. Use construction adhesive(plenty) to bond it all and it could be pretty effective.
I have a roll of stainless steel sheet metal so thin it can be cut with heavy scissors. I'm gonna be careful what I use it for-since it's stuff you can't usually find.