An (Incomplete) Experiment with Sensors

When you have lm-sensors installed on Linux, you can invoke sensors to list all detected sensors and their states. While it is generally of mild interest except when you suspect that something’s wrong with your box—or, more precisely, when you want to make sure something doesn’t go wrong.

Amongst the sensors, there are temperature sensors that gives you information about the chipset and CPU. You can also find out about fan speeds. So I wondered if could use the sensors to see if there’s a significant difference between when the computer is idle and when I am using it. I thought I could, maybe, also see temperature differences between day and night.

Filtering Noise (Part I)

If you own a car, you probably noticed that the speedometer needle’s position varies but relatively slowly, regardless of how the car actually accelerates or decelerates. Unless your speedometer is some variation on the eddy current meter, maybe the noise from the speed sensor isn’t filtered analogically but numerically by the dashboard’s computer.

Let us have a look at how this filtering could be done.

Cool, Baby, Cool

Not all computer cases are equally well designed. That, I’m sure, you know. The thing you may not know, is just how badly designed certain cases are. Not only are they hard to service, they can be detrimental to your hardware! I recently had to change the hard drive from my backup box and ended up changing the whole kit altogether because the old machine did not recognize the new 500GB hard drive. So I reused my old Compaq Presario 6400nx computer, which does recognize the 500GB hard drive, but makes it run very hot. I mean, very hot.

The new drive, although almost idling except for the nightly backup scripts and whatnots, got to 50°C. Even if 50°C is within the manufacturer’s expected operating parameters (10 to 55°C, or similar), that’s about 20°C more than my main workstation’s hard drive that runs around 30–35°C. That got me worried because it is well known that high drive temperature shortens its life considerably. So I decided to solve the problem using tie-wraps—no, not à la McGyver.