Post Feed
Comment Feed

About Me

My MP3 Player

Harry Potter and the Order of the Phoenix - (audio book) Dream Theater - Six Degrees of Inner Turbulence I am Legend - (audio book) Coldplay - X&Y

New Comments

2017 Archives

July All Archives...

High Definition Playback

Wednesday, February 4th, 2009

As a joint Christmas present to ourselves we bought a nice HDTV to replace our old 32" 300lb Sony monster. I had my home theater pc plugged in via svideo to the old TV because that offered the best quality for the available inputs. The new TV has a VGA connection (15 pin standard monitor connector) that I can plug directly in without having to plug into a converter to go from VGA to svideo. When I plugged it in and restarted the machine, it detected it right away and started running at 1920x1080! I'm pretty sure it was interlaced (1080i) rather than progressive, but that is better than the 640x480 I was running over svideo.

The machine seemed to be ok with running that high of a resolution, but MythTV's interface was a little sluggish with the remote. Playback of recordings and standard definition videos was fine, but playback of 720p or higher resolution videos wasn't working well at all; the machine was totally choking. Some videos would sort of play, the video would freeze while the audio kept going and every once in a while catch up for a few seconds. Some videos wouldn't play at all. I figured this would be a good time to upgrade it to take advantage of the nice new HDTV.

My home theater pc is basically an old Dell Optiplex GX260 with a 2.4Ghz Celeron processor. I had a hard time finding any information online about what processors would work with it, so I figured as long as it was a socket 478 with a Northwood architecture it would work. I was almost right. I found a Pentium IV 3.2Ghz with an 800Mhz front side bus (fsb) on eBay and "bought it now." When I put it in, it did work, but not quite as expected. The mainboard couldn't talk to the chip at 800Mhz, it only supported 400 or 533Mhz. Since the board was talking at 400Mhz (half of the bus speed of the chip) it was only performing at 1.6Ghz (half the cpu speed). This wasn't much better if at all than the Celeron I had in there to begin with. So finally found a P4 2.8Ghz 533MHz fsb chip really cheap on eBay and got that. Much better. I think this is actually the fastest processor I that will work in this machine.

In addition to the processor I upgraded the video card. This machine had some Intel video card built-in that just wasn't up to the job. I read online that Nvidia cards support some feature that allows the processor to offload some of the work to the video card which makes playback smoother for high bitrate high resolution videos. So I got an old Nvidia Geforce 6600. This is an old card with a VGA port, a DVI port and an Svideo port. I also got a DVI-to-HDMI toid so I could connect this to the TV using an HDMI connection eventually. The card worked great except for two little problems: the fan was going bad (like all video card fans since they face down) causing it to make noise and it had a habit of locking up the computer when connected to the TV using the HDMI connection. Maybe the locking issue is just a setting in the X server, but until I can figure that one out I'm running it over VGA connection. The fan was really annoying though. I got a new fan which is more quiet, but I can still hear it which bothers me. I checked the temperature of the GPU on the card with a fan running and it idles at about 65°c and goes up to 67ºc when playing a movie. I did the same without having a fan at all to see if it would survive, and it measured in at 112ºc (hot enough to boil water) after playing 30 seconds of a movie! I was astounded that the little fan was able to cool it down so much. I got a bigger fan off a carcass at work that did a better job. My thought was that a bigger fan could spin slower (with the right application of resistors inline) therefore being almost silent and still move the same amount if not more air than a little fan spinning faster.

htpc fans

The old and the new fan.

fan

I couldn't really find a good way to mount the new fan to the board, so zipties were needed. I was considering just duct-taping, but I didn't want to get sticky tape residue all over the card.

fan

The idea here is to blow air from the back of the card across the heatsink taking away the hot air.

fan

The fan is fed from the back.

fan

Once I hooked this up and test drove it, the GPU was idling around 73°c and hit 75°c while playing a 720p video. It's a little hotter, but MUCH quieter.

So after upgrading the processor and video card, I can now play 720p (sort of) videos and my home theater pc doesn't break a sweat. By "sort of", I mean transcoded video from full bitrate down to something like 6000Kb/s at 1280x720. Full 720p bitrates I believe are in the neighborhood of 15000Kb/s, but I have yet to find a sample video in that bitrate to test with. Full 1080p videos (think Bluray disks at 1920x1080) are way up in the 40000Kb/s area, so I'm not holding my breath that it run those.

Comments (3) Subscribe

Anonymous
#1 - Feb 12, 2009 at 8:25 AM
Nice, always been a fan of ghetto cooling solutions.
Joe
#2 - Feb 12, 2009 at 8:28 AM
Thanks! Maybe we wouldn't have to resort to such measures if they would just orient the cards so that the processor is on the top rather than the bottom when the card is in a tower case.
Anonymous
#3 - Feb 26, 2009 at 10:19 AM
Yeah, that's an issue for me too. But changing that would require the motherboards to shift the slots down about half an inch.

Make a comment!

Name
Numbers from below

Comment

Email Address

Website URL


Remember me