Noise Issues, just about solved!

YESSSSS, I am finally making progress after several weeks of this BS..

:D

So, I got those vinyl stand-offs, but bah humbug, if my casetronics cubid 2699R case doesn't allow for different stand-offs, like a traditional PC case does.. DOH! So scratch that.

BUT..

While I was disassembling my motherboard/case to do this, I had to yank my PCI sound card, or at least the PCI riser to get the motherboard free to pull out. So now instead of using nylon stand-offs, I basically ran the motherboard outside of the case...

NO NOISE!!!!!!!!!!!!!! WOOOHOOO!

So then I hooked it up to the PCI soundcard (Creative Labs Audigy 2ZS), and NOISE IS BACK! Then my dumb *** realized that the PCI card wasn't even hooked into the motherboard/riser!!

SO NOW I GOT IT! It's coming from the PCI card which is grounded to the CASE!

So then I put the motherboard back in and left the PCI riser out and used the on-board audio. NO NOISE STILL! So now I know that the sound is coming:

- In from power wire
- In to case which is grounded
- NOT into motherboard
- But into PCI sound card which is touching metal case in rear-mounted sideways PCI slot
- From PCI sound card out to RCAs out to Amp

So I have two options as I see it now:

1. Find a way to keep the PCI sound card from touching the metal case (how the F am I going to do this, any ideas guys?? Below is a pic of how it is mounted and looks).

2. Use onboard sound which isn't as good and doesn't have cool features like AdvancedHD and TimeCorrection/Delay... *sigh*

3. For those of you who think grounding the case would help, it does not. For whatever reason there is still noise, which essentially means that there is lower resistance through the PCI card, through the RCAs, into the amp, to the car chassis, than there is through a direct wire to the car chassis, which makes no sense whatsoever, but when I added ground wires to the pc case, it didn't help a bit so there is the laws of electricity being broken I suppose!! :(


The case setup with the riser looks like this, except my riser is for only one PCI slot. The PCI card slides in and screws into the back of the case itself. I think I would need to take the silver faceplate off of the PCI card itself, thus losing my port labels, btw, and then find some other way to secure it in place?? (= GHETTO! :()

http://www.mini-itx.com/store/images/c137-pci.jpg

I'm just glad this is all almost over with!

Also one side-effect of using the onboard audio is that now I get a turn-on thump when my PC gets power (not even powered on, but when the ITPS gives it the 12v power and before it gives it the turn-on command (3 seconds delay)). Any ideas how to avoid this? Maybe I need a 5 second relay for my amp to turn on? *shrug*

Also also now I have no clue what I'm going to do about my LCD, since it too is getting "noisy power" and is forwarding that through the VGA into the motherboard, which is even worse... UGH.

Quote:

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Originally Posted by sq_geek

1. Find a way to keep the PCI sound card from touching the metal case (how the F am I going to do this, any ideas guys?? Below is a pic of how it is mounted and looks).

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Paint the PCI card back panel with a plastic based paint or laquer? wrap it in insualtion tape where it touches the case? make a plastic shim in between the case and the PCI card? - just use some thin tranparent plastic like you get in food packaging or my old favourite when i used to make lightweight cases for my RC car electronics - boxer short packaging. You can still see the makings through the plastic then.

Andy

instead of covering the pci card with a non conductive material which is probably the easiest but if you ever change the card you will have to do it again, i would insulate the case where it touches, I would suggest a thick rubbery paint (like the stuff the guys dip there gps into to make it waterproof) or elsesome sealant like silicone or similiar.

How different is the sound with on board / pci ? I am using onboard and am reasonably happy with it, but cautious of spending another 150dollars (thats what it would cost me in this country) for external USB sound is the difference that much better ?

Well, I cannot say which is better wrt onboard or the Audigy 2ZS, but I would imagine the Audigy is at least a little better. It's not so much the quality that drove me to use a different sound card, it was the features, like I mentioned, Time Delay, AdvancedHD, and other 5.1 channel processing. That and it helps reduce CPU usage from my core PC, since the Audigy processes sound on it's own board, with it's own chips.

I'll try "shrinkwrapping" or otherwise painting the metal surfaces and see if that helps. It should only be a thin layer of metal about 4" worth which I need to "coat", so it should not be too much of problem..

So if this works, and the sound from the PC case and power wires are "blocked" from the motherboard and PCI soundcard, then what can I do about the noise from the LCD via the VGA cable? I'm 100% sure noise comes in from the LCD, as it is powered by the same noisy power supply (my car battery), and I'm 99% sure that that noise comes into my PC from the VGA cable. I just can't remember if it causes my sound card interference through the motherboard, or not, but IIRC it does.

So how could I block THAT noise? *siiiiiiiiiiiiiiigh*