Mobo: Ground on MDF/Plexiglass?

d_sellers1 · 10-09-2004, 12:19 AM

Looked through a few posts and found a few that applied.

My motherboard will be sitting on a peice of MDF. Normally a mobo would sit on brass risers to keep the board for short-circuiting it self out from touching the case. Since MDF (or Plexiglass) is non-conducting, does the motherboard have to be raised? Also I saw a suggestion in another thread saying to make sure each screw/ground point is grounded. Is that really necessary? Can't I just ground one or two points to one or two different grounds?

Derek

GruvThang · 10-09-2004, 01:11 AM

I would not mount directly to plexiglass it is a known generator of static electricity. All of the cases/installs I have seen use standoffs.

lawrence · 10-09-2004, 01:15 AM

what i have done is ground one stand off to the power supply case , never seemed to have any problems from this.
as far as raising th MB i have always raised it for air flow. once had a board that would shut down becouse it was getting too hot . just droped the exhust fan down do that it polled air from under the board and all was good.
also DO NOT use mdf to mount MB as it will expand and contract with heat and humidity and may stress the MB as it moves. and i have never used plexiglass so i dont know about staic, i have used urithane cutting board and it worked well. but if you cut the bottom of a case seems that will solve all of your needs - good ground , no staic and all mounting will not shift.

Speedpass101 · 10-09-2004, 01:20 AM

I am doing the same thing i got 1/4" plexiglass from home depot the case is going to be 17"x12"x5" I no its a little big but i can spare the room im running a micro atx p4. i mounted it with standoffs, it took a while but i got it. I got a 6-32 tap for like 3 bucks and it worked great for mounting the board. i am going to have a wire running to the psu case i was even thing of grounding the plexieglass to teh chassis of my car.

danon · 10-09-2004, 01:21 AM

Quote: Originally Posted by d_sellers1

Looked through a few posts and found a few that applied.

My motherboard will be sitting on a peice of MDF. Normally a mobo would sit on brass risers to keep the board for short-circuiting it self out from touching the case. Since MDF (or Plexiglass) is non-conducting, does the motherboard have to be raised? Also I saw a suggestion in another thread saying to make sure each screw/ground point is grounded. Is that really necessary? Can't I just ground one or two points to one or two different grounds?

Derek

as far as i'm concern there is no known issues regarding mdf except plexiglass as it conducts static electricity build up. so you can just screw your mobo straight to the mdf but somehow have some form of a piece of metal somewhere for ground when using plexiglass.

-i never could have imagined how billions of money spent, the lost of thousand of lives, just to put another country into chaos-

carpcnoobie · 10-09-2004, 01:47 AM

My current car PC (already working on the next version) is in a plexiglass case. It stands on brass stand-offs. I do not have a ground going to the power supply and I've never had a problem. However, I really don't see any harm at all in grounding it to the PSU.

As for the standoffs, yes I would definately have the standoffs.

danon · 10-09-2004, 02:17 AM

hey, i just checked mine and it has a standoff!!!

-i never could have imagined how billions of money spent, the lost of thousand of lives, just to put another country into chaos-

phc · 10-15-2004, 01:49 AM

The minute your power supply is connected to the MOBO, its grounded to the power supply (unless you happen to cut all the ground [black] wires).

Now, the question is, what is the power supply grounded to? Well, if its running off your battery, then its probably grounded to the car.

As far as standoffs, better to use them, it will give you some airflow under the PCB, which can help. Are they necessary? Probably not.

Regarding Plexiglas and static? Not much of an issue when you are grounded to the PS and CAR. When you just have the plexi and the mobo and nothing connected, just be careful with it - wear a grounding strap if you are in a low humidity environment. Don't run around the house with it while shuffeling your Nikes on the carpet.

d_sellers1 · 10-16-2004, 02:29 PM

Appreciate the info phc.

I'm not really going to attach the board to Plexi-glass but figured MDF and Plexi have some similiar properties.

I ended up screwing the mobo right down onto the MDF. Everything works fine. Just need to finish up with some stuff here and there...

Derek

GruvThang · 10-16-2004, 10:36 PM

good luck, keep us updated and pics would be nice for the visuallationally challenged!

TruckinMP3 · 10-16-2004, 10:43 PM

Quote: Originally Posted by d_sellers1

Appreciate the info phc.

I'm not really going to attach the board to Plexi-glass but figured MDF and Plexi have some similiar properties.

I ended up screwing the mobo right down onto the MDF. Everything works fine. Just need to finish up with some stuff here and there...

Derek

If you have any heat issues try the risers for airflow on the backside of the board, otherwise do not worry about it.