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This weekend I finally bought a membership for the QC Co-Lab, and took the opportunity to work on the TV Tuner modification I talked about previously.

Again, it’s a Hauppauge WinTV-HVR-950Q that I got from Newegg, and while I was using it, I noticed the main chip was getting hot.  While I can’t claim it had any noticable impact on image quality or performance, I just wasn’t comfortable with the casing becoming too hot to touch.  So I removed the casing and started watching TV to see which chip heated up.  That chip is pointed out here:

TV Tuner - Case Removed

Looking up the chip, it’s an Auvitek AU8522AA, the ATSC / NTSC decoder for the incoming signal. It makes sense that it would get so hot.  So the next step is to order the heatsinks, I chose these from Newegg. Once I had those, I tested them on the bare TV Tuner, and found I actually needed two:

While the larger chip was generating the majority of the heat, the smaller one heated up pretty well too.  Also, ideally I would’ve bought two sets of heatsinks, a larger set for the main chip, and then used the ones I have for the smaller chip.  But at $15 for these heatsinks, I wasn’t willing to spend more.

Next up was marking the casing for the holes.  Originally I had planned on using a stamp ink pad to mark the pins, and press that against the casing to determine where the holes should go.  I forgot to buy one, so I had to improvise on site with some thermal grease.

While I was discussing this with my friend Ben, he enthusiastically volunteered to start the drilling, so I took the chance for another picture:

Unfortunately that drill has a bit of vibration on it.  So the holes didn’t line up with the precision we were hoping for:

Not a problem, I just cleared out a larger hole to fit the entire heatsink through.

On the second set of holes, I marked through the thermal grease with some marker to help line things up.  The drill still had a lot of give though, so it wasn’t going to line up properly.  I had to re-drill the same holes several times before the entire heatsink would fit through.

I’m so happy that I got this shot, when I was mentally picturing this project, this is what I wanted.  Individual openings for each heatsink rod, with space inbetween to keep it inside and pressed onto the chip.

Unfortunately, the bases on the heatsink were taller than I expected, and I couldn’t fit the entire casing back on with the openings done this way.  So the second heatsink has a full opening like the first one.  Here is the final result, after I swapped the marked heat sinks for fresh ones:

While this definitely looks home made, I think it still looks clean and presentable.

As for the results of the mod:  Over time, the entire casing can still get pretty hot, the heatsinks themselves get too hot to touch after about an hour of watching or so.  Performance is effectively unchanged, since it was working correctly before this modification, but I’m much more comfortable with it knowing the heatsinks are pulling away a lot of that heat.

And also, if you want to see some other QC Co-Lab pictures, they are available in this Picasa album: http://goo.gl/USaNb

Thanks for reading!