2. A Fly In The Ointment Helps The Learning Process

Alas, once I hooked up two strands of coax cable to the inputs on the Hauppauge TV capture card, my system started crashing every 15 minutes whenever I used it to watch TV. A little quick forensics on the system showed that it was overheating after about that time. Using the "finger test" to see where the heat was coming from, it was immediately apparent that the arrangement of the dual-tuner card and that graphics card was trapping an enormous amount of heat. Eventually this was enough to warm the whole case to the point where the CPU would cross its temperature threshold - fortunately the motherboard default for this value was 60° C, so I did no damage to the system despite the high temperatures it sustained.

From this incident, I learned many valuable things about building media PCs, and about the issues inherent in building completely silent PCs. Because the kinds of media PCs I build usually include multiple optical and hard disks, as well as two tuner modules (sometimes on two separate cards, sometimes on one card), I have not myself attempted to build a passively cooled system. Invariably I’ve accepted the need for some active ventilation, and have decided to manage the resulting fan noise rather than trying to bring all this hot stuff together without actively moving some air across those heated surfaces.

I’ve also learned about the incredible value and quiet operation that high efficiency power supplies can deliver, and about the great suitability of mobile processors (and their motherboards) for media PC builds. I’ve learned who makes the quietest fans, and unhesitatingly and enthusiastically recommend the use of Nexus 92 mm and 120 mm case fans as the quietest around. (For a broader look at what’s quiet, check out fan coverage at SilentPCReview.com, a site managed by co-author for the aforementioned HTPC book, Mike Chin; for a good look at what quiet fans cost, visit www.endpcnoise.com.)

Two years later, in responding to an abbreviated version of the preceding story, Gear Digest Editor Barry Gerber asked me if I thought there might be an article somewhere in this learning experience. We decided to focus in on the heat output from TV capture cards, and to compare the heat output from the newer generation of adapters that feature much smaller and thinner tuner capsules, to the older generation of adapters that feature larger and thicker tuner capsules. In part, this should give us some sense of whether the new generation is less likely to produce sufficient heat to pose problems for passively cooled systems. It should also let us see how the new generation compares to the old in terms of heat output.