Ultimate Linux Box 2005

Some people wanted us to build a big powerful SMP system. Some people wanted us to build a silent machine that would be good for audio. So we did both.

Because we wanted the system to be self-contained and not depend on another server to boot, we installed a Sandisk 256MB CompactFlash card to boot from. This device looks exactly like another ATA drive to the system, so any PC motherboard will boot from it.

We considered using a USB thumbdrive, but that would have required some initrd drive juggling and GRUB wizardry. There are advantages to being able to pull your boot device out of the system and store it separately, but we didn't anticipate shipping the system through airports with drives loaded with encrypted confidential data.

If you plan to leave your silent Linux system on your network, you'll be a little more flexible in booting, and you can set up PXE booting. But if you want to take your Ultimate Linux Box over to a friend's house to play some music, you'll want to be able to boot independently. The Penguin crew plans to take this system to LinuxWorld Conference and Expo, and when you're wrangling hardware for a tradeshow one fewer thing to set up is good.

If you do build and install a silent Linux box, you'll probably end up doing a mix of both: NFS for user home directories, the company /usr/local/bin/ and other items that need to be in sync but aren't performance-critical. You can save your machine's own filesystems for big working files, like all the audio data you'll get from this system's high-end sound hardware.

Finally, to take even the keyboard clicking out of the silent system, Penguin founder Sam Ockman suggested a TouchStream LP keyboard, which works like a touchpad and requires no moving parts. It's also a pointing device and lets you map gestures to interface actions.


For the first time, we put professional audio hardware into the Ultimate Linux Box. What better place for a silent machine than the recording studio?

The RME Hammerfall HDSP9652 card we chose for this system is capable of up to 52 channels, and we matched it with an external box called the Multiface that brings out 8 1/4" jacks, as well as optical, coax and MIDI.

This card is as close as you can get to a “studio in a box”, because it's built around an internal mixer and allows you to route signals around inside the card with low latencies and low load on the CPU. Other features include the ability to “punch in” and “punch out” like a conventional tape deck.

Best of all, RME has been supporting the Advanced Linux Sound Architecture (ALSA) Project since 2000, so Linux users aren't second-class citizens. RME's site says, “ALSA support for the Hammerfall breaks the annoying chicken/egg principle—no professional hardware/driver, no professional software.”

Peter Todd covered the necessary tools for working with the Hammerfall HDSP cards in our October 2003 issue.

For video, we used a relatively low-end card (see the on-line Resources). We'd really like to start putting interesting and innovative video on Ultimate Linux Boxes, but there are still some issues with the drivers (see sidebar).

Thermal Management

So how do we keep this thing cool? First of all, it's important not to start tweaking with hardware combinations unless you know how to measure the effects that your changes have on the system's temperature. Don't change anything unless you know how to measure the effect of the change.

The good news is that the processor and motherboard vendors thoughtfully give us temperature sensors right on the key parts. And we can keep track of them using an all-important tool, lm_sensors.

We didn't have to measure drive temperature because we moved the drives to a separate enclosure, but smartmontools (see Resources) gives you an easy way to do that.

We ordered up some parts from Zalman, which offers a beautiful set of water-cooling hardware. The most visible part is the Reserator 1, a combined water reservoir and radiator that stands half a meter tall and holds 2.5 liters of water. Besides the Reserator, we also ordered one CPU waterblock per processor and matching tubing.

Thermal estimates showed that we wouldn't need a full Reserator per processor, so we used one Reserator per two processors and one for the power supply.

The Reserator comes with a 5W pump, which would break our beautiful silence, so it was time to convert it to operate purely by convection. In its stock configuration, the Reserator's inlet and outlet are close to each other, so we installed a tube inside each Reserator, running from the hot inlet to near the top.

What's that in your cubicle, Justin? We tested convective cooling with a scratch system and lm_sensors.

Did it work? The processor temperature climbed to about 50° C, then the tubes leading up from the processors to the Reserators warmed enough to start the convection. Temperature fell to 47° or 48° C in normal use, and running full-out, the system holds out below 50° C.

Cooling the power supply was a little harder. Zalman's beefiest fanless power supply is only 400W, and a big four-way board needs more. We decided to use the PC Power and Cooling Turbo-Cool 510 ATX.

We decided not to design and build a power supply for the project, since it's important to apply power to components in the right order, and we know PC Power and Cooling solved that problem for us. The cooling problem remained.

Enter the magic of metalworking. Phil brought the problem to a machine shop called Global Precision, and we had them do three pieces of work. They machined down the original fins of the power supply's heat sinks to create flat areas for attaching waterblocks. They made the waterblocks themselves—using blue anodized aluminum to match the Zalman parts. And they made two custom Y-connectors to split the water flow between the two heat sinks.

We removed the fan control board from the power supply. We didn't need it any more.



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Case with 2 - Motherboards?

Anonymous's picture

Anyone know where I can get a case that will hold at least two motherboards having expansion room for each, external cooling, and hot swap PSU, drives, CF support, etc? I see many doing case mods but nobody consolidating multiple systems in one CPU. I have seen a manufacturer with a commercial cabinet for as many as eight motherboards but it was not tailored to anything other than the commercial environment.

Each motherboard in the dual system could run VMware Workstation with one motherboard hosting failover firewall(dual), radius, LDAP, etc, and the second running multiple LAN clients. The option to one CPU with multiple boards is one high end CPU running VMware ESX or GSX which cost quite a bit more so the trade off is software vs hardware...but a box developed for ESX or GSX is going to cost far more than a dual motherboard system tucked into one CPU cabinet given the high end hardware solution will require 8-12GB of RAM on one board. The boards could each be populated with 4GB of RAM and dual core CPU. Your cost for _one_user_ with such a setup would be the cost for the systems and two copies of VMware workstation. I would think you could share the components of cooling and power at a minimum and there may be more. Why do this? So many cabinets...not enough processing power in one cabinet in residential systems but at this time they are cheaper to build.

Great modding article.

Step one?

Porges's picture

You guys seem to have skipped something on the way to building your own Ultimate Linux Box... where to get the money!

To build a comparable system would likely need the backing of a few (or many) sponsors, would it not?

Boot drive options

philiph's picture

When I built my custom wan router (August 2004 Linux Journal article 'Point to Point Linux'), I went through a similar decision about the boot drive. While that system is quite a bit different, the goals are the same: reliability and minimized heat output. I chose a 256mb flash ide drive from MagicRAM because we had some problems with the CF-IDE adapters we tried. The MagicRAM device plugs right in to an IDE connector as a small dongle. On the downside, it is more expensive than CF/IDE solution.

I also was able to shrink a stock Fedora Core 1 distro down to a size that ran comfortably off the 256mb disk. That of course requires throwing out all graphical components and other extra stuff, like man pages and localization. Still, it is completely possible to get a good working Fedora environment in that space. That may be a more robust solution since it's more 'standalone' than having to depend on network booting, etc.

One thing you have to be careful about in that situation is moving all your log files and other temporary data to a tmpfs. Flash devices are great but individual memory bits can only handle a few hundred thousand writes before dying. Thus its important to minimize continuous writes like log files.

Ultimate Linux Box

Romuald's picture

This is a wonderful, insightful and uplifting case of a revealing infrastructure implementation of Open-Source & Free Software.
Keep up these useful pieces.

I was wondering about the Res

Anonymous's picture

I was wondering about the Reserator 1, how it was modified to allow cooling by natural convection. I understand they took out the pump and attached a pipe to the inlet port, which then went up through the reservoir. Makes perfect sense, thermodynamically, and I wonder why Zalman didn't think of this in the first place (even without removing the pump). All you get now, without the pipe up, is a lot of turbulence in the reservoir (or is that good?)

Anyway, anybody have any idea how hard it is to make that modification? Did it require some serious custom metalworking just like they did to the power supply, or is this something an average DIY can do in his garage?

Also, Zalman has the Reserator 2 out, which has coolant hose connectors that seal when you take them apart, so you don't have to mess with clamps anymore. Anybody knows if this restricts the flow of coolant seriously enough to prevent effective natural convection?

Very nice case

jsroy's picture

What really caugth my eye when I looked at the Linux Jounal is the incredibly cool case for this machine. It then made me think of my lame desk, and that my machine deserved better. Finally, it made me want to build one (or maybe even commission one) for myself.

So I was woundering if anybody would know how or where I could get plans to build a cool custom case?

Also, I have tryed to look into the "www.woodentemple.com" site to look at the craftmans works, but can not seem to get there. Is the site not built yet?


More nice cases

Vaino Husgafvel's picture

Go to www.mini-itx.com and at right You see several projects.
Click any of them and enjoy and be INSPIRED !

Best Regards


Very nice case

jsroy's picture

What really caugth my eye when I looked at the Linux Jounal is the incredibly cool case for this machine. It then made me think of my lame desk, and that my machine deserved better. Finally, it made me want to build one (or maybe even commission one) for myself.

So I was woundering if anybody would know how or where I could get plans to build a cool custom case?

Also, I have tryed to look into the "www.woodentemple.com" site to look at the craftmans works, but can not seem to get there. Is the site not built yet?


Touchstream LP Keyboard

chrisg's picture

Curious about this device, I looked it up on Google (since you didn't include it in the parts list, I didn't know the manufacturer). I found this interesting note on the home page at www.fingerworks.com:

Important note!

FingerWorks has ceased operations as a business.

I was actually hoping to try them out...

I have one...

Anonymous's picture

While the interface is kind of novel, and gesturing to replace the mouse is nice, it wasn't the best $400 that we ever spent. I can touch type fine but my speed never improved on it to the point that I'd consider shelving the regular keyboard. After a couple weeks of having both a normal keyboard and the gestureboard on the desk at the same time, it moved up to the shelf, where it stayed, except when I try and fob it off on friends who invariably return it.