Depending upon the details of the mechanical parts, cases, and pressures, negative pressure situations can cause unfiltered air to be sucked in through the smallest openings, including the front of optical, floppy, and tape drives, leaving a dust coat on the interior of the devices.
For optical drives, dust on the optics can degrade performance, but is typically corrected by using a commercial CD cleaner to clean the optics. But there are also a few mechanical parts that are inaccessible from the front, and I wonder how dust might affect them. Here is an example of ingestion.
As far as I know, disk drives are well sealed, so dust should not be an issue.
Floppies obviously have a gaping exposure to dust intake, as do tape drives (not common in desktop systems, but I have one).
That pretty much leaves fans as the remaining item with moving parts, and I've seen nothing about dust accumulations affecting fans.
I get 193 search hits in SPCR forums on "dust", and I'm sure that most of them are like the ones I've read over the months here, just mentioning dust in passing as something obviously to be avoided.
Has anyone plausible notions or personal experience with ingested dust causing mechanical problems?
Specific relevant links are
http://forums.silentpcreview.com/viewtopic.php?t=7630 (search for Yamaha on the page) which documents dust ingestion in optical drives.
and this post in a CD forum.
There have been some comments elsewhere that even with positive pressure, airflow will deposit dust. True, if the air carries dust, but a positive pressure case with filtered intakes and a dust-free interior should deposit little or no dust. Or have others had different experiences?
