Doug's Quiet Wood Case Mk II - HTPC Edition

Gorsnak · Post by **Gorsnak** » Thu Sep 28, 2006 6:03 pm

So I recently put a bunch of zoomy new parts into my wood tower case (see gallery thread) and I have all the parts of the old socket A system sitting on the coffee table. Now it occurs to me that the old system would run MythTV very nicely with the addition of a Haupppage dvr card and possibly a larger hdd. I'd just need a case. Thing is, htpc cases capable of holding full atx motherboards are, umm...rare? Anyways, it seems to me that it would be fun to build another case. This time the goal is something sleek glossy black that would look nice in a stack of home theatre equipment. This places a hard constraint on width at 17.5" and makes shallower preferable to taller. With an atx mobo the only possible way to get the psu on the back plane would be to tip it on its side, which would push the height up to ~7.5" (current design is 6 3/8"), so I'm thinking of a slightly unconventional layout:

MSI K7N2-G board
Athlon XP 2100+
512MB ram
Gigabyte 6600GT
Seasonic Super Tornado 400
WD Caviar 80GB (may be tossed for a newer larger quieter drive, depends on how audible the whiny bastard ends up being)
Hauppage PVR 500 (the only new equipment)
could possibly have a sound card added at some point

All exhaust is on the right side. A 120mm fan moves air from the cpu area, and the psu sits sideways venting air through large slots. This means the power cord socket will have to be removed, longer wires added, and mounted seperately on the back. A dvd drive will be stealthed into the front. Power switch and led positions are not yet final. The finished product will have routered edges (3/8" radius, probably) and a gloss black finish. Material is 3/4" mdf sides and 1/2" mdf top and bottom, though I might yet decide to go 3/4" or possibly 5/8" all around in spite of the height penalties for doing so.

The main intake is at the rear between the silentpipe 6600GT and the hauppauge dvr card. Smaller intake ports are cut just above the rear I/O panel and on the left side next to where two hard drives can be suspended below the dvd drive.

And a shot from the front with the dvd drive removed for visibility. The psu is softmounted high enough that the bottom intake is unrestricted, with exhaust ducted to the vent slots.

So, comments, ideas? I'm not entirely sold on my airflow plan, but the size constraints limit the layout a great deal. I'll be putting the thing on rubber feet, so I could theoretically go with a seperate bottom intake for the psu. I don't think the system will generate enough heat to make psu spin-up an issue, though, and with the horizontal layout meaning no convection to move the warmer air to the exhaust fan, a few more total cfm through the case seems like a good idea.

All the moving parts will be softmounted to try to avoid resonance issues, and since this thing will be sitting with audio equipment I'll probably bow to the EMI whiners and put in some sort of foil shielding. It would make for a shiny case interior complimentary to the black exterior if nothing else.

peerke · Post by **peerke** » Fri Sep 29, 2006 3:26 am

I would split up the interior in two sections: A cold chamber and a warm chamber.
The cold chamber would have the air flowing from the intake beside the HD's through the PSU and out through the slots. This is to keep the components that need to stay cool actually staying cool.
The warm chamber would have the air flowing from your proposed rear-intake over and around the GPU and through the CPU out the side. All these components will be all right running at high(ish) temperatures without negative effects.

I've been contemplating a similar build but instead of using MDF I'm planning to use stacks of plywood showing the lamination as a front.

Gorsnak · Post by **Gorsnak** » Fri Sep 29, 2006 11:12 am

Thing is that the dvd overlaps the motherboard by 1 1/4" plus the length of the power molex (the dvr card possibly overlaps the dvd as well, but I don't have exact dimensions for that), so I can't put any physical barrier between the front and back of the case unless I make it substantially deeper or fold up some elaborately shaped cardboard thing. With both the case fan and psu contributing to cfm through the case, I don't anticipate that it will get very hot inside. It's not like running MythTV is going to have the psu and gpu loaded very heavily.

Tibors · Post by **Tibors** » Fri Sep 29, 2006 7:50 pm

This isn't really that elaborate IMHO. Besides, if you use something more sturdy than cardboard, then it is a nice attachment point for the DVD and the HD suspension.

It's not that I think your case would get hot without it, but the airflow close to the HD's will be better with this I think.

Gorsnak · Post by **Gorsnak** » Fri Sep 29, 2006 8:36 pm

Hmm. You missed slots for the ide cables, but that's an idea. I was thinking of going around the back of the dvd drive, not just butting against the bottom.

The dvd drive is hanging from the top, though, can't be attached to a hypothetical divider. The plan is to have the bottom and back one piece, with most items attached to it except for the dvd and switches/leds. The front/top/sides is a second piece, allowing for the possiblity of having no seams visible on the thing assuming I get the kind of finish I'm hoping for. But the dvd has to be attached to the top/front so that it can be stealthed with a chunk of mdf on the front of it, etc. Not sure that really has any implications for a airflow divider.

Tibors · Post by **Tibors** » Sat Sep 30, 2006 6:59 am

Gorsnak wrote:But the dvd has to be attached to the top/front so that it can be stealthed with a chunk of mdf on the front of it, etc. Not sure that really has any implications for a airflow divider.

Just make the gap bigger than the drive and line the edges with soft foam.

If you don't already have the DVD drive, then you might want to look into slot loading slimline drives. They are nor cheap, but ...

Gorsnak · Post by **Gorsnak** » Sat Sep 30, 2006 11:54 am

I'm starting to like the idea. Due to space constraints it'd have to have a psu cutout too, but in a way that's a good thing, as it could double as the support holding the psu up off the case floor, and the side of the short duct to the exhaust slots. It would leave the hard drives and dvd as the only heat sources in the front chamber (and the psu of course, but it doesn't contribute to heat in the chamber itself as its heat is exhausted directly). The 120mm exhaust fan then only has to deal with the gpu and cpu heat, while in the old configuration of this equipment the same fan handled that plus the drives while the psu was off all by itself. It also makes for more directed airflow than without the divider, and it was the undirectedness of the original design that was bugging me. Two exhaust points, three intake points, and hopefully the air moves in a useful pattern. This pretty much forces the air to move in a useful pattern. Only question is if it would lead to stagnant warm air pooling up in the top of the front chamber with the psu taking air in from the bottom - especially worrying because the Tornado has small vents in the front and pushes a small portion of heat out in that direction.

Slot-loading dvd is a great idea. Cheapest I've found from a Canadian retailer so far is this Liteon, which is already stretching the budget at $127 + shipping compared to $40 and no shipping for a basic drive from a local shop. Plus it's an external usb drive - not necessarily a problem, I guess, so long as it can move enough data to stream a movie. I'm going to look more, because that would look very nice and be much easier to pull off than stealthing a regular one.

Gorsnak · Post by **Gorsnak** » Sat Sep 30, 2006 12:10 pm

Found an internal IDE Liteon slot drive at Frontier for $95. Very tempting.

Tibors · Post by **Tibors** » Sat Sep 30, 2006 12:28 pm

Gorsnak wrote:Only question is if it would lead to stagnant warm air pooling up in the top of the front chamber with the psu taking air in from the bottom - especially worrying because the Tornado has small vents in the front and pushes a small portion of heat out in that direction.

Is the PSU hanging above the edge of the mobo? If not, flip it upside down. Solves the support problem too, since it can rest on the bottom of the case. Though that might give problems with routing the 20-wire power cable.

Gorsnak · Post by **Gorsnak** » Sat Sep 30, 2006 12:53 pm

Well don't you just have all the answers.

Why the hell didn't I think of that? I've got a little clearance between the mobo and psu. Not much, but should be enough. A little experimentation suggests that the atx power connector has just enough length. I think I might move the front chamber intake onto the bottom of the case, too, to try to contain hdd noise a little better.

peerke · Post by **peerke** » Mon Oct 02, 2006 10:43 am

Gorsnak wrote:I think I might move the front chamber intake onto the bottom of the case, too, to try to contain hdd noise a little better.

It's starting to sound

better and better. Keep us posted on your build and, possibly, the resulting temperatures and noise.

Gorsnak · Post by **Gorsnak** » Mon Oct 02, 2006 12:24 pm

Oh, don't worry, there will be updates and pictures and details galore. Currently the project is a little stalled trying to verify the nature of a Liteon 831S dvd drive. My BIL's supplier rep says it's a tray load, in spite of being described as "slot-in" and looking for all the world like a slot load in every picture I can find.