Some notes on creating a home theater PC using the Acer Aspire Revo

 

Important
This is a heavily edited version of a post that originally appeared on a blog called The Michigan Telephone Blog, which was written by a friend before he decided to stop blogging. It is reposted with his permission. Comments dated before the year 2013 were originally posted to his blog.

This article was originally published in January, 2010. Things have changed considerably since then, and most of what was shown in the original article is no longer necessary. You install Ubuntu, then you install XBMC, and it pretty much just works. And if you want an even better experience, you might want to look into installing XBMCbuntu. There may be a few hints in this article that are still applicable but you are very likely going to find that most things just work. One thing you may (or may not) need to do is completely uninstall and then reinstall lirc, because it may not show you the window that lets you select your remote (assuming you have purchased an infrared remote that has a receiver that connects to the USB port), and on the re-install of LIRC you should see the selection window and be able to pick your correct remote.  Or, better yet, you can skip the removal/reinstall by running dpkg-reconfigure lirc from a terminal prompt (which will bring up the remote control selection window).

Another thing that you might want to do is consider using Linux Mint rather than Ubuntu, particularly if you hate the new Unity interface.

The original genesis of this installation was an article at the Lifehacker site entitled Build a Silent, Standalone XBMC Media Center On the Cheap. While that article is probably outdated, you may still want to read it first, then come back here.

The first thing you need to know is that there are several different models of the Acer Aspire Revo out there.  You want the highest powered model you can get, and in particular, the most memory and highest number of processors.  Even the high-end ones are very reasonably priced if you shop around, and even moreso if you can score a good, gently-used unit.  Note that you CAN buy an Acer Aspire Revo with some version of Windows installed, but it will cost you more and (especially in the higher end models) and for a standalone media center, Linux works better anyway, so why pay extra for an operating system you may never use?

You’ll need a wireless or USB keyboard and mouse during the setup phase.  Some Revo sellers include a wireless keyboard and mouse, while others don’t, so just be aware of that when ordering. Read specifications VERY carefully and know what you are buying! Also consider, if you get a defective keyboard (we did), will it cost more to ship it back than what you’d spend to buy a replacement locally (probably yes, if you buy from an overseas seller)? Don’t overlook pre-owned Revo’s — as long as they are still in good working condition and have a model number in the 3000 series or above, they should be fine (the main thing to make sure of is that they have the maximum amount of memory). Be aware that some early models did not have a digital audio output, so if that’s important to you (and it probably is in this application), be careful what you buy.

Also, the Lifehacker article wants you to install the operating system from a thumb drive.  If you have an external CD or DVD drive (that connects using a USB port) do yourself a favor and use that (just install from the distribution CD). By the way, speaking of USB ports, at least some Revo models have a sixth (hidden) USB port. It’s right next to the power switch, on the narrowest part of the case — if you see a small, rubbery insert with a USB logo on it, you can peel that off with your fingernail to reveal the hidden USB port (not that you’d want to unless you really need the sixth port).

Probably the most important thing in that Lifehacker article is the BIOS tweaks. Note that most newer Revos don’t seem to have the “Boot to RevoBoot” option, so if you can’t find that setting, don’t worry about it. Also, if you get a newer, higher end unit with more memory, set the iGPU Frame Buffer Size to 512MB, not the 256MB that the article suggested for the low-end unit that Lifehacker used for their build.

Installing Ubuntu is easy; you basically answer the few questions asked during the installation, and stay with the defaults when you are not sure how to answer. You probably do want it to take over the entire hard drive, so make sure you have saved anything you might want from that drive before you begin the install. We strongly recommend using a 32 bit version of Ubuntu – even though the Revo technically supports a 64 bit operating system, we have found that many things simply don’t work right with the 64 bit OS. If you insist on trying the 64 bit version, you’l probably at the very least need to work through several issues.

If you’re totally inexperienced with Linux, you probably should grab the latest full install disk image of Ubuntu and burn it to a CD, or if you really want to try installing it from a USB memory stick, a visit to the Pen Drive Linux site may help you get the image onto the USB stick in the first place. We used the Ubuntu Minimal CD Image for the install, to save time downloading a huge CD image that is mostly replaced during the software update process. If you go that route, be sure to read the instructions on that page carefully, or you’ll be scratching your head wondering why it’s not working! When you type “tasksel” to select the system to install as instructed, you’ll want to install the standard Ubuntu Desktop but there may be other options you’ll want to install as well, such as an ssh server and/or samba server (those might already be present in the Ubuntu desktop install, but it won’t install anything twice, so I just checked those to be on the safe side).

If you do as most users probably will, and download an ISO file, burn it to a CD, and install from that (using an external CD or DVD drive), just be sure that you check any boxes to install additional codecs or to use additional repositories, if offered any such options.

After installing the operating system, if the nVidia drivers were not installed (very unlikely unless for some reason your video hardware wasn’t detected properly), the next task is to install them.  The system should offer to do this automatically (look for an icon in the top panel).

You can install Software using the Ubuntu Software Center, but not all available software is available there. You can also install Synaptic if you wish, from the Ubuntu Software Center or using apt-get install synaptic from a terminal window. When I mention installing software, I suggest you try the Ubuntu Software Center first, and if you don’t find it there, then try Synaptic or apt-get.

You might want to start by installing mc (Midnight Commander) – I wouldn’t have a Linux box without it, but that’s just me.

In newer versions of Ubuntu you may also want to consider installing ClassicMenu Indicator, which is a notification area applet (application indicator) for the top panel of Ubuntu’s Unity desktop environment. It provides a simple way to get a classic GNOME-style application menu for those who prefer this over the Unity dash menu. Like the classic GNOME menu, it includes Wine games and applications if you have those installed. It looks like this:

ClassicMenu Indicator
ClassicMenu Indicator

If you want to be able to access your HTPC from other computers on your local network using SSH, install openssh (you don’t need to do this if you installed an ssh server using the minimal install, or if you find that ssh already works) and (optionally) sshguard.  Then edit /etc/ssh/sshd_config and change the PermitRootLogin value from “yes” to “no” (for the sake of system security).

Another thing you want to do is make sure that the system time be kept synchronized with Internet servers.  Right click on the clock applet in the top panel, then select Time & Date Settings, and make sure everything looks right there (especially that the option to set the time “Automatically from the Internet” is selected).

Now it’s time to install XBMC.  If you don’t find it in any of the standard repositories or want to make sure you get the latest release version, then do this from the terminal window:

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

You might also want to install MythTV, or at least a MythTV frontend. See Links: A complete guide for setting up MythTV from start to finish for more information on that. Note that MythTV can be installed from the Ubuntu Software Center, and that’s the only recommended method, since they tend to offer a more stable version.

If you happen to have a Wii remote control, see the document Building an ION powered HTPC with XBMC and in particular, Module 6 : Using a Wii remote control. The following notes on an IR remote do not apply if you are using a Wii remote!

If you have an infrared remote control and infrared receiver (these generally come together as part of a package; check the XBMC forums to see which are recommended), run XBMC at least once and then run dpkg-reconfigure lirc from a command prompt (terminal window) to select your particular model of remote control.

You will likely want to be able to launch XBMC using the remote.  As a PRELIMINARY way to accomplish this, we opened or created (can’t recall which) a file called .lircrc (note the leading dot character) in the user home directory and put the following lines in:

begin
 prog = irexec
 button = KEY_BLUE
 config = xbmc --standalone &
 repeat = 0
end

begin
 prog = irexec
 button = KEY_POWER
 config = /usr/bin/gnome-session
 repeat = 0
end

begin
 prog = irexec
 button = teletext
 config = sudo shutdown -r now
 repeat = 0
end

This starts XBMC if you push the blue button on the remote.  It also returns to the desktop if you push the power button (however, it may leave whatever program you were in running in the background), and reboots the system if you push the teletext button, but for the latter to work, you must add the following line to the end of your /etc/sudoers file:

%admin ALL = NOPASSWD: /sbin/shutdown

EDIT:  In later versions of Ubuntu the above line does not always work as shown, however, substituting the user name for %admin apparently does.  So for example, if you had users named larry, moe, and curly on your system, you could do this (if you wanted all of them to be able to use the remote button to reboot the system):

larry ALL = NOPASSWD: /sbin/shutdown
moe ALL = NOPASSWD: /sbin/shutdown
curly ALL = NOPASSWD: /sbin/shutdown

Note that this is just to get you started — you can do more complex operations by running an external script rather than the selected program directly, to make your remote work the way you want it to.

By the way, the irexec program must be running for the above to work, so you can use the Ubuntu Startup Applications program to make it run at startup. You should run it with the -d option, e.g. irexec -d in order to make it run as a background process.  Note that you need to do this even in newer versions of Ubuntu.

Startup Applications — Add Startup Program
Startup Applications — Add Startup Program

You will probably want to set up one or more shared folders on your system so you can move videos, etc. into those folders. Be aware that you do have to enable file sharing for each folder you want to share.  This is pretty straightforward in Ubuntu — select the folder you want to share, right click on the folder icon, click on “Sharing Options”, and then give the share a name and check the appropriate boxes:

Folder Sharing options
Folder Sharing options

Check “Share this folder” and give the share a name (I called this one “shared”). Check “Allow others to create and delete files in this folder” even if you are going to require a valid login to do so, otherwise even you will not be able to copy files to that folder or delete existing ones from a remote location.  Check “Guest access” if you want anyone on your local network to have access without the need to supply a user name and password.

If you are trying to get VNC screen sharing (in Ubuntu it’s called Desktop Sharing, but it’s actually VNC) to work, when setting up Desktop Sharing Preferences, make sure that “You must confirm each access to this machine” is UNchecked (it is checked by default).

Desktop Sharing Preferences - UNCHECK "You must confirm each access to this machine"
Desktop Sharing Preferences – UNCHECK “You must confirm each access to this machine”

Then, use the CompizConfig Settings Manager (see How To Change The Settings Of Ubuntu Unity With CompizConfig Settings Manager) and uncheck all the options under “Effects” (except that “Window Decoration” is okay to keep). Apparently, the use of any visual effects is enough to make the remote desktop non-functional:

CompizConfig Settings Manager — Effects
CompizConfig Settings Manager — Effects

The nice thing about this is that even if you have the overscan issue discussed below, when you access the shared Desktop you see the full screen including the top and bottom panels, so you don’t have to guess where you’re clicking! In theory, you could disconnect the keyboard and mouse from the Revo, and just use the Remote Desktop when you need to do system maintenance work, or whatever.

One major issue you may encounter when using a HDTV as the display device is something called “overscan” – that means the desktop is actually larger than the area shown by the HDTV display, meaning you can’t actually see your top panel, etc.  While XBMC has a ways to correct for overscan, it’s better to correct it for the entire system.  In recent Ubuntu versions, the NVidia drivers are installed when Ubuntu is installed (probably only if the installer detects you have NVidia graphics hardware), and the newer drivers do sometimes expose an Overscan Compensation slider that can be used to correct the problem:

NVIDIA X Server Settings (Overscan Compensation slider near bottom)

This slider doesn’t always appear for some reason, and even when it does, you really should try NOT to use it (except, perhaps, during initial setup and configuration) because if set to anything other that “0” it WILL degrade picture quality somewhat.  The proper place to cure overscan is at the HDTV itself.  Most HDTV sets have a setting that will fix overscan, but the problem is that there is no standard name for this setting — I’ve seen it called things like pixel-to-pixel, dot-to-dot, 1:1 display, exact image, etc.  It’s often buried a submenu or two deep (remember that owner’s manual you got with your TV?  Now might be a good time to dig it out!). I’ve found that if you look hard enough, most newer TV’s have this setting, although some do a pretty good job of hiding it (the Sharp LC-42SB45U being an extreme case – it won’t even display the option unless the timing of the signal you send meets certain specifications!).  You really should try very hard to find this option, because it’s much better to correct the problem at the hardware end than by using any software method (that includes the software overscan correction built into XBMC) – you’ll get a sharper picture and quite likely fewer issues with video flickering, etc.  Even if you have to resort to building an xorg.conf file to make it work, that’s better than trying to do software overscan compensation in the video driver or XBMC — use that method only as a last resort.

If your TV set just doesn’t have a setting such as the one mentioned above — and some don’t — there is a page of instructions to help fix the overscan problem here.  We originally wanted this for the aforementioned Sharp LC-42SB45U TV and wasted a huge amount of time trying to find an overscan fix, and you can read what we finally came up with for that particular make and model TV only here: An overscan fix for the Sharp LC-42SB45U television set when connected to a computer with a Linux operating system (Ubuntu, etc.) (and if you have that model TV, it’s preferable to use the xorg.conf file given at that link rather than the Overscan Compensation slider). No matter what, you can see the full screen if you use the VNC/Desktop Sharing service mentioned above, and some have even resorted to using a little workaround to make the overscan less annoying, assuming you don’t find the workaround more annoying than the original problem! And for the more technically astute, it’s always possible to tinker with the ModeLine in xorg.conf (which, again, is preferable to using the Overscan Compensation slider).

Note that the following few paragraphs (up to, but not including, the one about HDMI audio issues) were applicable at the time this article was originally written, but are likely no longer valid due to updates in the nVidia driver and in Kodi (the new name for XBMC).

Irregardless of whether you have overscan issues, if (and ONLY if) you can see any flickering or “tearing” or other weirdness during video playback, it would probably be a good idea to follow the instructions one of these three posts: Either Howto achieve judder free perfectly synced playback at 23.97/59.94 Hz, XBMC and fixing the 24p issue, or HOW-TO setup XBMC and Linux with correct resolution (xorg.conf) (and I’d recommend them in that order — start with the first, and only go on to the second or third if you still have unresolved issues, except that if after trying the technique in the first link, you still see a bit of flicker during the playback of video files then I’d jump right to the third link — that’s the one that fixed it for us on one installation) — in those articles they tell you to modify /etc/X11/xorg.conf and add a couple of lines. I’d suggest a few additional modifications there, if not already mentioned in whichever article you used — under Section “Device” add one or both of these lines

Option "HWCursor" "false"
Option "DynamicTwinView" "false"

The first of those lines is a “blinking cursor fix” and it’s supposed to help if you find an unwanted blinking cursor you can’t get rid of (I haven’t encountered that particular problem yet). The second line enables 1080p 24Hz mode for smoother playback of certain videos (probably most of them, actually). That line can actually go in either “Device” or “Screen” section – I added it to both just to be safe, but that’s probably overkill. Also, at the bottom of the xorg.conf file, add this:

Section "Extensions"
     Option         "Composite" "Disable"
EndSection

That’s supposed to provide better H264 acceleration.

If you added the “DynamicTwinView” “false” option as shown above, and you know for a fact that your monitor supports 1920 x 1080 @ 60 Hz (you should be able to determine that if you followed the instructions in the aforementioned post) then that mode should become available in XBMC — in the XBMC GUI, go to Settings | System | Video Output to select your desired output mode, and see if that mode is available. If, for some reason it is still not available, you might be able to force the issue (you really should not need to do this if you started with the posts linked above, but I’ll leave this information here anyway in case someone needs it) – in order to do that, open a terminal window and do this:

cd /etc/X11/Xsession.d
sudo touch 45custom_xrandr-settings
sudo nano 45custom_xrandr-settings

Paste into this file the following lines, but take the parameters for the first line from the Modeline you created in the previous step, except use “1920x1080_60.00” instead of “1920×1080”.  The first line below is an example (do not copy it verbatim, use the settings from your Modeline) but the second and third can be copied and used as is:

xrandr --newmode "1920x1080_60.00" 173.00 1920 2048 2248 2576 1080 1083 1088 1120 -hsync +vsync
xrandr --addmode default 1920x1080_60.00
xrandr --output default --mode 1920x1080_60.00

One other thing that might improve the video quality in XBMC is to go to Settings | Video | Playback settings and change the setting Adjust display refresh rate to match video to On start/stop (you could also try Always). This fix may be of particular help if you are trying to watch Live TV, or recorded TV from a PVR backend, and the picture doesn’t appear quite as sharp as it should. Leave Pause during refresh rate change set to Off. Obviously, this would be most noticeable if you are trying to view a 1080p source. In some areas you may need to play with the de-interlacing options as well, but that is beyond the scope of this article, and we didn’t find a need to do that.

If you are having audio issues when trying to send audio via HDMI, first of all open a terminal window and enter alsamixer and when it comes up press F6 to select your sound card (most likely HDA nVidia) and then make sure that none of the S/PDIF outputs are muted (this will me indicated by “MM” whereas an unmuted one will show “00”). Pay particular attention to S/PDIF 1 as it is often the culprit – use the arrow keys to select it and then press M to unmute it, then ESC to exit. I know this doesn’t make sense since you are trying to send audio out the HDMI port and not the optical audio port, but trust me, you need to do this. Then, if you are finding that audio is coming from the wrong speakers (center and LFE channels are mixed up with left and right surround channels) go to this page: HOW-TO:Remap HDMI audio on Gen 1 ION – Linux – I suggest using the settings under “1.3.1 ALSA Configuration” and below, but read the entire page first to get the full overview. Note that after following the instructions on that page, if you are also running the MythTV frontend you may have to set the audio to use ALSA:hdmi_direct and that this will NOT appear in the dropdown – you should first select one of the other compatible HDMI card options and then edit the Audio Output Device field to show ALSA:hdmi_direct. This is all necessary because the NVIDIA MCP79/7A HDMI hardware has incorrect channel mapping. This problem does NOT appear when using the S/PDIF (optical) output.

If you want to use a web browser to view videos that require the Flash plugin (such as many YouTube videos), particularly if you will be trying to view them in fullscreen mode, you should know that the Flash plugin will not use the Revo’s onboard nVidia graphics unless you tell it to. But, if you don’t do that the videos will most likely be too jerky to watch. So here is what you need to do from a Linux command prompt:

sudo mkdir /etc/adobe/
sudo nano /etc/adobe/mms.cfg

Now insert the following two lines into the file you’ve just opened:

EnableLinuxHWVideoDecode=1
OverrideGPUValidation=true

Then press CTRL+X followed by Enter to save the new file.

Note that this fix does not work absolutely perfectly, so you might still see some video issues now and then, and it might not work on all sites or in all browsers (it does work in Firefox, however). In many cases the video will be far more watchable than without the fix, but on some systems this fix could cause browser crashes and if those become frequent you may need to try removing the /etc/adobe/mms.cfg file. Also, note that this fix will only improve videos played using the Flash plugin.

If you need to (re)format a hard drive to use with your system, and you don’t want any wasted space on the drive, be sure to read this: Free Disk Space by Reducing Reserved Blocks

If you want your system to have a fixed IP address on your local network, click on the networking icon in the top panel (up and down arrows side by side), then Edit Connections, then find the connection you are using and edit it appropriately. For example, under the Wired tab I see Wired Connection 1, and if I click on that and then click the Edit button, I can then select the IPv4 Settings tab, change the method to Manual, and then enter the appropriate settings for my local network.

You may find that you need to go to the “Misc” section of /etc/samba/smb.conf and set domain master = no — otherwise you may find that certain network shares randomly disappear from other computers on your network. If you don’t have the problem of shares disappearing from other computers on your network, or if you don’t have any other servers or computers that are also trying to assert themselves as a master browser, then this may not be an issue for you.

If you have Macs on your local network and would like to use AFP (Apple File Protocol) to move files around, see How to set up AFP filesharing on Ubuntu.

If you hate typing in a password each time you ssh into your Revo, see Stop entering passwords: How to set up ssh public/private key authentication for connections to a remote server.

If you want to reduce startup time when using Ubuntu or Mint (and you do not have more than one operating system installed), do this:

sudo nano /etc/default/grub

Then look for this line:

GRUB_TIMEOUT="10"

Change this line to read:

GRUB_TIMEOUT=0

Then follow the instructions at the top of the file: “If you change this file, run ‘update-grub’ afterwards to update.” This also must be done as root, so after you save the file and exit nano, do this:

sudo update-grub

If you allow the Update Manager to install certain types of updates (particularly nVidia driver updates) — and you should update your software when updates are available — you may find that XBMC won’t start up, but instead displays a message that stats with the words, “XBMC needs hardware accelerated OpenGL rendering.” Typically, simply rebooting the system will fix that issue.

If you are using the Perl script we posted a couple of years ago that monitors a Linksys or Sipura VoIP device and provides Caller ID popups when a call comes in, you may be interested to know that by adding one line to the Perl script and making some minor configuration modifications, you can also have Caller ID popups in XBMC. See our article BETA Perl script for Caller ID popups when using Linksys/Sipura devices for information. Alternately, if you have an Asterisk server, you can send Caller Id information to XBMC by adjusting the XBMC configuration as in the aforementioned article, and then adding a line to your Asterisk dial plan in the form:

exten => extension-number,n,TrySystem(wget -b -O /dev/null -o /dev/null "http://HTPC-IP-address:8080/xbmcCmds/xbmcHttp?command=ExecBuiltIn&parameter=XBMC.Notification(Call%20from%20%22${URIENCODE(${CALLERID(name)})}%22%2C${CALLERID(number)}%20calling%20extension-number%2C15000%2C%2Fhome%2Fusername%2Fphone.png)")

Note that is all one line, and be sure to change the bold, italicized values to something appropriate for your configuration, and also be sure to see the aforementioned articles for XBMC configuration information and to get the phone.png icon.

If you would like to occasionally play music without the need to have the TV running, you might want to install a program called Audacious. The nice thing about Audacious is that it offers a LIRC plugin (under the General plugins section) and if you enable that, and then add a section to your .lircrc file (for an example, follow this link and then scroll down to the section “Configure Audacious(2) to use Lirc“), you can control the program using your remote.

Audacious Preferences

If you set Audacious to “Continue playback on startup” (under the Playback section of the preferences), and then create a .lircrc entry to start Audacious, you could use your remote to turn on Audacious and resume wherever it left off on your playlist.  This is really beyond the scope of this article, but I just thought I’m mention it for those who have your Revo hooked up to a receiver and would like to be able to play audio without wasting electricity running a TV you’re not watching.

Addendum for those who wish to use Boxee under Ubuntu 12.04:

Boxee has discontinued support for desktop platforms, but you might be able to install the last Linux desktop version by following the instructions on this page to install Boxee (note particularly the unmet dependency that must also be installed), and then if you are using a MCE remote, you must also follow the instructions in this post to make the remote work correctly with Boxee.