CPU upgrade on eMachines EL1300G-02w

I am using a EL1300G-02W computer as a HTPC using MythTv.

It would play back 720p HD video just fine with the original processor, but couldn’t quite commercial flag new recordings in real-time while also watching a live feed. [This wasn’t a big issue, as I very rarely watch new recordings live.]

Even though it works working perfectly fine as a MythTV box with the original processor, I had been keeping an eye open on Ebay for a replacement X2 (dual core) processor for the AM2 socket.

I was limited to CPU’s that produced 45W or less of power, which basically means the “e” line ( 4450e, 5050e, 4850e, BE-2400, 3250e). These types of processors had been selling for $50-60, but then I lucked out and found an an AMD Athlon X2 BE-2400 2.3 GHz Processor which I was able to get cheaper than average ($32 w/ shipping!).
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Low power (CPU) visualizations for MythTv / MythMusic

I recently checked out all of the music player visualizations for the MythMusic module (part of MythTV). They vary widely in CPU usage and visual appearance. I wanted the CPU to be at least 50% free to work on transcoding or commercial flagging in the background while music was playing, so I avoided the especially fancy ones. I also found that the ones that used OpenGL used small amounts of the CPU (as they offloaded much of the processing to the GPU).

Selected visualizations (good effects, but minimal CPU usage):

  • blank (83% idle, not much happening on-screen ) – This is the ultimate “low power” visualization, against which all others are measured. The fact that it takes my computer 17% of it’s CPU time to play ogg vorbis files should indicate why I’m somewhat CPU conscious.
  • Album Art (70% idle)
  • Squares (75% idle, simple but classy)
  • lv_gltest ( 40-60% idle, 3d histogram)
  • Gears (60% idle, simple)
  • lv_flower (50% idle, very nice!)
  • madspin (30-50% idle, fast and sparkly)

Here is a list of visualizations that might be worth the extra CPU hit based upon their cool visual effects:

  • BumpScope (20% idle – roving spotlight on embossed scope)
  • Goom (20% idle, space tunnel effect)
  • oinksie (0% idle, kind of cool)
  • infinite (0% idle, but looks good!)
  • corrona (0% idle, falling/flowing effects)
  • jess (0%, but very very cool!)
  • jakdaw (0% idle, psychedelic flowing water effect)

I suggest avoiding the following visualizations, as they use too much CPU for what they produce:

  • monoscope (40% idle, one red line)
  • SterioScope (30% idle, two red lines)
  • lv_scope (20% idle, white scope on black background)
  • nastyfft (20% idle, bars, almost 3d look scope) – Use lv_gltest if you like this one
  • bumpscope ( 0% idle – slightly faster movement than BumpScope, ball rolling left/right) -Use BumpScope (with capital letters) for less CPU usage, and better effects.

The following three visualizations gave me problems:

  • analyzer (crashes computer in fullscreen!)
  • Synaesthesia (40% idle, but no visible output?)
  • Spectrum (80% idle, simple spectrum scope w/ colors, looks weird in fullscreen)

Mythexport not working with mythbuntu

If you are getting ERROR: AtomicParsley type messages in your mythexport.log file, it may be because ffmpeg isn’t exporting the files correctly. One reason for this is that config’s in mythexport that have spaces in the name cause problems. The workaround reported here is to remove the old config, rename it into something that doesn’t have a space, and then re-create the user-job using the new config. (For good measure, I made sure the user-job didn’t have spaces either.) After this, be sure to re-start the mythtv backend to make your changes take effect.

MythTV power usage

Switching to an eMachines EL1300G computer drastically cut the running power consumption of my MythTV setup, to an average of 45 watts when idle. (The old computer used 141 watts when idle.)

This makes it practical to leave the computer on 24/7. I had set my old computer to shut itself down when not recording, but this required a 2 minute boot-time wait anytime we wanted to watch TV. (When it was not already awake recording a show). Even when the old computer was off, the constant current draw from the other devices (UPS/HDHomeRun/Amplifier) was 17 watts.
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eMachines EL1300G-02w – HTPC with MythTV on Linux

Executive Summary: The eMachines EL1300G-02w is a good choice for a low power home theater PC (HTPC) or media computer. Pros: Small form factor, low energy use, low noise with stock fans, DVD-DL R/W +/- optical drive, lots of media card readers. Cons: 160GB stock HD will need to be swapped out for back-end use, VGA video out (only), Analog Audio out (only), minimal expansion capabilities.
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Setting up lircd with the hdhomerun and a Tivo series 2 remote

To set up lircd with the hdhomerun to see a tivo series 2 remote control, you should first program the HDHomeRun to send UDP packets to your linux computer with a command such as the following:

hdhomerun_config <device id> set /ir/target "<lircd ip addr>:<port> store"

You can test that this is working by running:

irrecord -H udp -d 5000 "testing"

If you get dots when you press your remote control buttons, the HDHomeRun is sending IR information to your linux box. (remember to unblock UDP port 5000 for incoming transmissions if you are running a firewall!)

Once that is working, just set up your /etc/lirc hardware.conf and lircd.conf files to support the Tivo series 2 remote.
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How to move a mythtv database from one machine to another

Backup the database on your source machine. Newer versions of mythtv do this for you automatically. Check out the mythconverg_backup.pl script if you have to do it manually.

Delete any existing database on your destination machine:

$ mysql -u root
mysql> DROP DATABASE IF EXISTS mythconverg;
mysql> quit

Re-create the empty database on your destination machine:

$ mysql -u root < mc.sql
(You may need to use the -p option and enter your root password)

You may also have to set up the mythtv user with the correct password:

$ mysql -u root < mc.sql UPDATE user SET Password=PASSWORD('YOURPASSWORDHERE') WHERE user='mythtv'; FLUSH PRIVILEGES;

After this, run the mythconverg_restore.pl script:

mythconverg_restore.pl --filename mythconverg-1214-20091010150513.sql.gz

You may have to specify hostname, database name and enter the password if you don’t have a mysql.txt file set up in my .mythtv directory. You may also have to specify the fully qualified path to the file if it’s not located in your default backup directory.

How to add XBMC to MythBuntu 9.10 (or Ubuntu 9.10)

Xbox Media Center is no longer for just the XBox. It’s UI is slicker than MythTV’s Frontend for playing music, videos, and showing slideshows of pictures. (It’s weather applet is also much nicer…) If you have an existing Ubuntu 9.10 based system, the PPA:team-xbmc repository makes it dead easy to install xbmc on a ubuntu computer with the following commands:

sudo add-apt-repository ppa:team-xbmc
sudo apt-get update
sudo apt-get install xbmc
sudo apt-get update

MythBuntu doesn’t support AutoIP

MythBuntu (and Ubuntu I assume) don’t support the AutoIP standard.
(Auto IP is basically a way for devices to form ad-hoc networks…if you don’t have a static IP, and are not assigned a dynamic IP via a dhcp server, you try out a random address in the 169.254.x.x network ( netmask) and as long as ARP doesn’t report a conflict, you now have your IP!)

Windows, and the HDHomeRun devices support this, but MythBuntu 9.10 does not. So, I’m back to using firestarter to easily configure my MythBuntu box to assign the HDHomeRun an IP address via DHCP.

Discovery Error 4001 : Silicon Dust HDHomeRun error

SiliconDust HDHomeRun Discovery error 4001I was in the process of changing out my MythTV backend machine, and when configuring the new machine, I took a look on SiliconDust’s website for a firmware update for my HDHomeRun (HDTV Network tuner box). I hadn’t updated it since late 2008, and sure enough, they were five or six firmware versions farther along. (Up to 20091024 to be specific.) So I upgraded the box using the newest version of the hdhomerun command line utility under linux. Everything went fine until the HDHomeRun rebooted. After that point, the utility said that an error occurred discovering the HDHomeRun! I tried booting into windows to try out the windows software, but it also could not discover the device, and gave me this ominous message:

Discovery Error 4001: Please email support@silicondust.com
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