Noisy EEPC fan

I have an Asus Eee Box PC 1033 connected to my TV via HDMI and it runs Kodi. Even though I do clean this mini PC regularly, it was making a loud hum since the last couple of days. Thinking it might be getting too hot, I checked the temperature using sensors command it showed normal temperatures.

~$ sensors
coretemp-isa-0000
Adapter: ISA adapter
Core 0:       +49.0°C  (crit = +100.0°C)
Core 1:       +49.0°C  (crit = +100.0°C)

Then I opened up the cover and booted it. Right from the start, the hum was there and as temperature doesn't go up that fast, I focused on the heat sink and cooling fan assembly. I unscrewed the 7 screws (2 each for heat source of the heat-sink, and 3 for fan housing). The fan was a DC Brushless Model KSB0505HB - found in many laptops. After removing the cover on the fan and removing the rotating blades, all that was required was cleaning the axle of the blades and adding some lubrication to it. 

Closed up the fan cover, and screwed the heat sink and fan assembly back in its place. After booting the PC, the hum of the fan was back to normal levels and temperatures were a bit down too as I took the opportunity to put some new thermal paste on CPU and GPU chip.

In case you want to do similar job to your PC fans, a quick YouTube search and review of those videos will help you.

Fixing DVD/CD drive which won't open

I fixed my DVD drive in my PC today. It had not been used for a long time (3+ years) and was originally purchased in 2010, if I remember correctly.

Issue: DVD drive would not open using eject command or the eject button on the drive.
Behaviour: When using eject command or button, the drive makes a "thud" kind of sound and then tries other things to test what is loaded and the busy indicator LED stops blinking after several seconds. Physical ejection of the tray works fine.

TL;DR: Change drive tray eject pulley belt.

After searching various forums and trying out different flags with the eject command, I saw this post and I thought I might as well give it a shot as the software eject methods had failed. Also, it was an excuse to shutdown the PC and give a thorough spring cleaning.

While I forgot to take the pictures of the work done, it isn't that difficult to perform. The LG DVD drive just had 4 screws at the bottom and three locking wedges for the face place. Once the 4 screws were taken off, the bottom plate came out easily by lifting it from the back and the easily taking it off from the bottom wedge. Next was the face plate which I tried to take out by unlocking the 2 side-wedges but it was not coming out easily. Then, I thought to ejecting the try out manually first - I used a straightened paper clip to push in the "eject hole" of the drive. When I tried opening the face place with the tray out, it came out easily.

At this point I was thinking of disconnecting various connections to remove the large circuit board that I could see but I realized by chance that the whole mechanism could come out without disconnecting the mother board. Removing the drive mechanism and turning it around - top part on top, showed me the motor and pulley for the drive tray.

I touched the drive belt and it did not have the softness that one would expect from a rubber belt. When I tried to move the pulley, it did not reliable move the belt along with it. This indicated that the required tension was not there and also the friction between pulley plastic and belt had reduced due to aging.

I replaced the belt with a rubber band of slightly smaller size that the pulley itself. Tests by rotating the pulley were successful. So were the eject commands after reassembly of the DVD drive. The DVD drive is working normally now.