inverted motherboard - any cons?

Enclosures and acoustic damping to help quiet them.

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DyJohnnY
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inverted motherboard - any cons?

Post by DyJohnnY » Thu Jul 14, 2005 11:17 pm

I've been looking to build an own case, out of wood for an A64 system, and i've come to the following guidelines...but first the system description

Epox 9nda3j
venice 3000+
Xp90+120mm fan
gf 6600gt
2xcdrom
2hdd's
Bluestorm 400W

Here are the guidelines:
-Any holes and vents will have to be either in the back of the case or in the floor. no side holes.
-All noise sources should be as far away from the user as possible, considering that the case will be placed to my left on the floor, and I am left handed, and DVDRW drives are easier to open, because the eject button is on the right of the drives.
-PSU on bottom of case, in a separate chamber from the rest of the case.
- Chamber will only be traversed by a bottom air duct torwards the front of the case, probably to cool hardrives and provide intake for the whole case.

Upper chamber:
Here's the dillemma... If i invert the motherboard, the CPU fan will be facing torwards me.
It will be more advantageous in cooling the 6600gt, but i'm worried about the tradeoff regarding CPU fan.

Also i was thinking of ducting the RAM+CPU area...with a tunnel but i think the gain will be minimal because of the Xp-90 design :(..but that's another idea...i'd like to know first, what do i stand to lose if i invert the motherboard.

Kalel83
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Post by Kalel83 » Sat Jul 16, 2005 6:02 pm

if you are going to build it out of wood, you are going to have to purchase the heaviest (and most expensive) you can. also you could add tar paper or some other type of weight.
Wood resonates from the vibrations of the harddrives,fans so forth. suspension on bungie cords-rubberbands or something would be advised.. if not a must. including for the motherboard
rubber stripping between the boards...
otherwise it could sound like a harmonic washing machine
suspend it off the floor as well with some sort of thick but soft rubber feet or somethin
filter the intake, and make sure the intake and exaust holes are nowhere near eachother/not on same side- against a wall/corner
you don't want a loop of airflow between intake and exaust
just my opinion..

jamesm
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Post by jamesm » Sat Jul 16, 2005 10:11 pm

look at drums - those are made out of wood and they are extremely loud.

DyJohnnY
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Post by DyJohnnY » Sun Jul 17, 2005 12:09 am

well, i've got it all figured out i guess... i don't know how the type of wood is called, the one i'm using that is... it's basically woodust "glued" together. in romanian it's called...in free translation... "crowded plates of wood"...but as i said it's sawust glued together....and it's heavy, much heavier then a regular case.
I know the problem with resoance, i will suspend as many components as i can, i think i can do that even with CPU fan.
PSU will be in separate chamber on a base covered with soft+absortbant material. I've experimented with this on my desk, it is made out of wood ofc, and the results are promising.
I have striped an old case for the MB support frame, PCI support frame and drive frames, the are sitting on my desk now, desktop style, and i'm happy the motherboard does not seem to transmit vibrations to the desk.
I'm worried more about the DVD drive, but i'm confident i can isolate it very well in the end.

my biggest question mark is wehter i should do convetional or inverted MB placement, having all noise sources as low to the ground as i can sounds in theory better than PSU at bottom, CPU at top, GPU in the middle.

swivelguy2
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Post by swivelguy2 » Sun Jul 17, 2005 4:05 am

DyJohnnY wrote:well, i've got it all figured out i guess... i don't know how the type of wood is called, the one i'm using that is... it's basically woodust "glued" together. in romanian it's called...in free translation... "crowded plates of wood"...but as i said it's sawust glued together....and it's heavy, much heavier then a regular case.
That's called particle board, in the US at least.

PositiveSpin
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Post by PositiveSpin » Sun Jul 17, 2005 5:04 am

There's particle board, and then there's MDF - MDF isn't sawdust glued together - it's more like paper glued together - I think the American term is "kraft wood".

Lots of speaker manufacturers use MDF for their cabinets because it tends not to resonate, and that's a good thing for what you are doing.

As to whether to put the motherboard upside down or not - if the motherboard is normal way up, then the hottest component (CPU) is at the top, so it is not heating up the boards in the slots. That's good, but it does mean that a super-hot graphics board might be heating up the CPU...

If the motherboard is upsidedown, then the CPU's heat will rise and possibly heat up the boards. If you duct the CPU, then that shouldn't happen. Other than that, no, there's no reason to avoid mounting the motherboard upsidedown. I have 3 Lian-Li V1000 cases, and they work fine - the motherboard is upside-down in the V1000 design.

HTH

NeilBlanchard
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Post by NeilBlanchard » Sun Jul 17, 2005 6:10 am

Hello:

It's called MDF here in the states, too: Medium Density Fiberboard. It is probably the best thing for this situation -- except that it won't provide any RFI shielding. It does take paint very well -- it is used to make trim, paneling, cabinets. It should not be confused with MDO, which essentially plywood with a paper surface...

DyJohnnY
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Post by DyJohnnY » Sun Jul 17, 2005 1:17 pm

ok, the material i have is part sawdust, part splinters if u can call them that, and they seem glued together, i have no clue how it is made, but for example my panasonic 5.1 speakers are made of the same thing, and their boxes don't resonate. i thought, since it's a bunch of stuff put together, it doesn't have a specific resonant frequency like normal wood. RFI shielding..well i'll get to that when it will upset my other appliances, right now the PC is on the desk, and has not generated interference.

i've been thinking about this idea "invert the MB or not", and i've come to the conclusion i will invert it, there are more advantages to it.
am also planning to make the tunnel that will provide air to the CPU, but due to the annoyance called Xp-90 fins + RAM orientation[ i want to cool them too - it's an overclocked system], i will have to make the tunnel shift in a horizontal plane.
the airflow diagram will look like this, viewed from the side

........AGP.AGP.AGP...
<-<-<-<-<-<-<-<-<
....................^^^^^^^^^^
.........A.......120^^...DDDD
.........T.........XP-9^...DDDD
.........X.........XP^^...DDDD
.........P.........X^^^^^^^^
.........W............\.\.\.\.\.\.\.\
.........R.............[120mm120]

D- dimm slots

steef
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Post by steef » Sun Jul 17, 2005 1:57 pm

The inverted setup allows you to have your exhaust fans in the side panel (the side not facing the user of course). Your setup could work with three 12 cm fans in the bottom as intake. For greater airflow another three exhaust fans in the side panel can be added.

Also consider having the PCI slots and IO-panel downwards. Because of the bottom intake, you need to have some ground clearance anyway.

Consider having the harddrive in line with the PSU. Above your motherboard you will probably save some space for a dvd-drive - the total height of motherboard + dvd-drive approximates the total height of PSU (15 cm) + harddrives (it depends which side of course, but I'll take length).

If you use 'higher' front and rear panels, you won't need feet below the case.

I would appreciate pic's of proto's / finished item.

Good luck!

http://www.stefanreijmers.nl/doc/www.st ... l-93_1.jpg (schematic w/o fans)
http://www.stefanreijmers.nl/doc/www.st ... l-93_2.jpg (schematic with fans)
Last edited by steef on Mon Jul 18, 2005 3:36 am, edited 1 time in total.

DyJohnnY
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Post by DyJohnnY » Sun Jul 17, 2005 10:55 pm

i guess when u said the side fan thing u thought the case would be to the right of the user...well i'm lefthanded and perhaps not only that but i thought about my PC as beein to the left of me [that's why the idea of inverted motherboard sounded a bit weird, cuz i will be closest to the fans if i invert it]. Also i've set out to have fans only on the floor and back, no front intakes, no side intakes/exhausts.
I will raise the case on feet, rather than it's whole body, because if it will be one thing for sure, it will be heavy, and because swinging and moving a heavy thing by tensioning it's support frame might turn out bad, i'd rather put armchair wheels on the bottom of the case.
Also you seem to want the case to be rater small. i am thinking this case as able to support a future [1-2 years] watercooling system, therefore i want to be as generous with the space as i can.
I've worked out some final sizes. It will all be about 60cm high, 22cm wide and 45-50cm long.
As for the pictures, they will surely come, right now it is one big pile of ideas in my had, and one big plank of wood sitting behind my bed.

lenny
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Post by lenny » Sun Jul 17, 2005 11:09 pm

One downside to inverting the MB is that if you're using heatpipes, they may be in the wrong orientation (hot end should be above cool end).

DyJohnnY
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Post by DyJohnnY » Sun Jul 17, 2005 11:14 pm

don't think it's the case here, Xp-90 when mounted, has pipes parallel to the ground, so it doesn't matter wether i mount the motherboard upside down, i can invert the HS on the CPU and it wouldn't make a difference if it was mounted normally.

steef
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Post by steef » Sun Jul 17, 2005 11:52 pm

@DyJohnY

The design I suggested actually has the exhaust away from the user if the user has the PC to his/her left side.

The design can be used without fans since none of the hot components are in line (except for the harddrives and the PSU). This requires something like a NCU-2000 to cool the CPU however.
Instead you can use upto 3 parallel 12 cm fans as intake. If that is not enough you can have 3 parallel 12 cm fans as exhaust (exhausting away from you). But you can stick to a single 12 cm fan too ...

From your remarks I noticed I ahve to explain why I suggest to have the exhaust in the side panel. It is because I want the air to move in a straight and natural line. Idealy bottom and top would be open, but an open top is not practical. A very large exhaust opening in the side panel is the next best solution in my opinion. With the exhaust in the rear the airflow has to do a much tighter bend, which might lead to pockets of hot air and turbulance.

(The design can be made taller to provide more room).

My main suggestion however was to have the IO panel facing downwards - what do you think of that?

DyJohnnY
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Post by DyJohnnY » Mon Jul 18, 2005 12:11 am

ah ok, now i got it, could not picture what u said but now i understand...well in my case it does not work, i have a bluestorm= 120mm fan on it's belly. from your diagrams i would have to place the bluestorm on it's belly, not on the side, like u have drawn it. as for the motherboard with connectors facing dowwards...donn't u think it will be a problem connecting different cables? biggest concern is the monitor cable, that has the stupid habbit,in my case at least, to break 1 or 2 wires, and then u lose one of the colors to your monitor.
other than that it's pretty good idea, especially puting the harddrives torwards the back of the case. you could improve the design and make the HDD and the PSU change places, and open up an intake below the newly positioned hdd's , that way, hdd's have some air going and are placed futhest away from the CPU.
biggest question is how hard will it be to connect/disconnect stuff...if it's a pc that will not move once setup it could work very well.

steef
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Post by steef » Mon Jul 18, 2005 3:35 am

If you already have a PSU with a 12cm fan, you could consider to remove the case ... (not everybodies cup of tea ...)

The ease of connecting stuff and staying connected is definetely better with the IO to the top. You are right about that. I have found a solution too: Imagine the connectors pointing upwards, above that you can have an angled inner wall acting as gutter for the cables towards the rear of the case and guiding air to side exhaust at the same time. The top compartiment - which can contain the dvd drive too - can be made to open seperately from the case, so you have easy access to the connectors.

I guess I should spend a sketch to it later today ...

steef
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Post by steef » Mon Jul 18, 2005 12:21 pm

http://www.stefanreijmers.nl/doc/www.st ... l-93_3.jpg

The sketch I promised ... It should be seen as a front view/cross section of the case. The red symbolises the intake fan(s), the blue the airflow. Motherboard to the right with the IO shield pointing upwards. The angled inner panel is a gutter for cables - which are led to the rear - and at the same time it helps airflow. The top compartment can be accessed from above in case connections have to be changed or added.

~El~Jefe~
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Post by ~El~Jefe~ » Mon Jul 18, 2005 6:18 pm

jamesm wrote:look at drums - those are made out of wood and they are extremely loud.
my drums are made out of steel :P

~El~Jefe~
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Post by ~El~Jefe~ » Mon Jul 18, 2005 6:25 pm

I was thinking about this, about wood cases, it really could work well if you use the RIGHT wood.

find the most dense wood that has a lot of rosen in it.

i suggest a fruit tree wood. thick slabs of it.

I wouldnt use synthetic compressed wood, it is a fire hazard and is toxic when heated in general.

I dont think it would resonate all that much to be honest if you use a thick slab of very heavy wood. get lots of knots in it, it wont resonate a whole lot if you suspend hd's and fans are on low speeds.

jamesm
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Post by jamesm » Mon Jul 18, 2005 8:20 pm

~El~Jefe~ wrote:
jamesm wrote:look at drums - those are made out of wood and they are extremely loud.
my drums are made out of steel :P
my drums are made of birch. :)

~El~Jefe~
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Post by ~El~Jefe~ » Mon Jul 18, 2005 8:29 pm

I love birch sticks. such a nice light thunk.

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