Silent MythTV Box


Introduction

My first MythTV system was built in 2004 using an Asus Pundit-R barebone chassis running Debian unstable. It soon became something no-one in my household could live without. However, even though the Pundit looked nice, it was a bit too noisy for the living room. It also had little room for expansion on top of a single TV tuner, wireless card and hard drive. Annoyingly, it was very small and fiddly inside - not at all fun to tinker with.

I also wanted to move to Ubuntu, which provides a great compromise between being up-to-date but stable. So, I decided to build a completely new box. I thought long and hard about the various options available when choosing the hardware. Barebone systems are cheap, easy to build and nice looking, but they offer little room for expansion and are tricky to customise - if you don't like the power supply then you're pretty much stuck with it. Epia-based systems are a good choice, but they don't offer much bang for your buck. I also didn't want a separate frontend and backend, as this can be expensive to build and run. Plus, you've got two systems to keep up-to-date.

The layout of my front room means that there's an alcove close to the TV which is hidden behind a chair. It's a perfect size for a tower PC so I decided that the best solution was to go for a full-sized midi tower. This would leave plenty of room for cards, hard drives and DVD drives, would be easy to work inside and be cheap to upgrade. All I had to do was make it as silent as possible. Here's how I did it...

Components

Overview

The system featured on this page is now 5 years old, which is a lifetime in computer terms! However, it's still going strong and I still use it as my main media PC. Much of the hardware is outdated, but hopefully you will be able to apply some of the concepts to your own system and get as much use out of it as I have from mine.

Case - Antec SLK2650-BQE

This is the cheap version of the Antec Sonata and is supposed to be a quiet case, so boasts rubber grommets on the fan and hard drive mounts. It's not the flashiest case around, but looks quite stealthy and does the job. It's also quite cheap, but with decent features; screwless optical drive mounts, thumb screws, quiet 120mm fan etc.

A good alternative would be the new Sonata III, which comes with a near silent PSU as standard.

Motherboard - Gigabyte GA-K8NSC-939

This board's NForce3 chipset and AMD socket 939 are now very out-of-date. If I were buying now I'd go for a socket AM2 motherboard with PCI-express graphics and a passively cooled northbridge as standard.

Processor - Athlon64 3000+

This was the entry level Athlon64, but still has plenty of power for Linux and MythTV. The other great thing about it is that it runs very cool - idling at only 25C with the stock HSF. It also has AMD's PowerNow! technology, allowing its CPU frequency to be throttled when idle.

Things move quickly and nowadays you can get a single or dual core Athlon64 for a fraction of the price I paid. While dual core is not essential, for the money I'd say that it's probably worth it.

Memory - 1GB

I initially built the system with 512MB of memory. However, after a while I noticed that it seemed to take ages to "spring to life" each time I used it. There was a definite delay bewteen the first few keypresses on the remote control and the response from the menus. This was due to the running frontend software being swapped out to disk and having to load back into memory. Adding a second stick of RAM to give a total of 1GB completely resolved the issue and the system is now instantly responsive and generally faster.

The fact that I use the standard Gnome desktop definitely has an impact on memory usage and I'm sure you can get away with less memory if you use Xubuntu/XFCE (or if you're feeling hardcode, Evil WM or ratpoison).

Hard Disk Drive

I've ended up with 2 drives in the system just because I had them available. If I were building from scratch I'd probably just go for a single 500GB drive. 250 hours of recording space should be enough... until HD of course :-)

Update: I now have a 1.5TB and a 2TB disk in the system to keep up with the growing content!

Power Supply - Seasonic S12 380W

The Seasonic is a great power supply and the 380W version is reasonably priced. Its absolutely silent, slow-rotating 120mm fan is the only one in the system.

In order to make the most of the PSU fan, I modded the case by removing the rear 120mm fan, blocking the side vent and removing the plastic fan holder from the front of the case. This should allow the air to flow in though the front and back of the case, over the CPU heatsink and out through the PSU.

CPU Heatsink - Scythe Ninja

The stock HSF performed really well, but was the noisiest component in the system. I'd read that the Scythe Ninja could passively cool my Athlon and knew that this was the only way to make a completely silent system. With no fan on the Ninja and the case fan disabled, the idle temperature rose from 25C to just 31C. This is amazing considering the fact that the only active fan in the system is the 120mm fan in the bottom of the PSU.

The Ninja looks fantastic, but it's massive; the biggest CPU heatsink you can buy, dominating the inside of the case. Installing it was not easy - it required the motherboard to be removed from the case, the standard HSF mount to be detached and a metal plate to be attached to the back of the motherboard for support. It went smoothly, but is a scary experience, especially as the stock HSF was so welded to the processor that removing it also yanked the CPU from its socket, bending one of its pins! Luckily, it still worked... :-/


Zalman ZM-NB47J Northbridge Cooler

After installing the Seasonic and Scythe, I was disappointed to hear that the noisiest component left in the system was the northbridge fan on the motherboard. I thought of just disabling it, but decided to play it safe and replace it with a passive Zalman heatsink. Fitting it was pretty easy, although it required removing the motherboard yet again!

Once the Zalman was fitted, I powered on the system and my heart sunk... nothing happened. Then it POST beeped and I realised that it was actually on! Complete silence. Job done.

With hindsight I'd just buy a motherboard with a passively cooled Northbridge as standard.


Zalman ZM-2HC1 Heatpipe HDD Cooler

While building the PC, I'd noticed that the hard disk ran pretty hot. This concerned me, as there were no longer any case fans to dissipate the heat. Also, even with the rubber mounts of the Antec case, the hard drive was clearly audible, with low, rumbling noises reverberating through the case.

There's also a bit of a design flaw in the Antec case which features just two silenced mounts - in adjacent bays. So, I decided to kill three birds with one stone and install a Zalman HDD heatpipe cooler. This great looking device fits over the drive and can be mounted into a 5 1/4" bay using large rubber spacers. In theory, this should cool and silence one drive and also move it away from the other drive.

Unfortunately, due to the Antec's "clever" 5 1/4" screwless mechanism, the Zalman just would not fit into any of the bays. It's also not cheap and I was left wondering if I'd wasted my money. Then I had a brain wave. The rubber spacers can be fitted to the bottom of the drive, so I mounted the drive on a rubber mat on the bottom of the case. This resulted in a completely silent and cool solution.

After a year of use I'm very happy with this setup; the hard drive is completely silent and I've had no problems at all.


Inno3D Nvidia GeForce-FX 5200

The 5200 is widely regarded as the graphics card to use with MythTV. I learnt this the hard way when ATI dropped support for my Radeon 9250! Hopefully now that ATI belongs to AMD and they've released the drivers as open source this will soon change.

Note that the 5200 is getting a bit long in the tooth nowadays. So, especially if you have a PCI-express motherboard, you may be better off going for one of the newer cards such as an nVidia 6200 or 7100 GS. They work just as well.

Logitech S510 Keyboard, Mouse and Remote

I've recently added a Logitech S 510 wireless keyboard, mouse and remote. These work over RF rather than IR, so have an amazing range. The keyboard and mouse are perfect for hacking away while sitting on the sofa. However, the remote is useless because most of the buttons don't work under Linux. This doesn't bother me because it has very few buttons anyway and would be a poor replacement for the Hauppauge remote.

Conclusion

After 5 years of constant use, the system has been completely reliable. The only problem being the case fan causing vibration and rattling the side of the case. This has been treated by padding the side door. It's not bad when this noisiest component in your rig is the case itself!

All in all, I'm really pleased with the result - a cheap, reliable, easy to install, completely silent system with lots of room for expansion.


Complete System Specification