+<table class="dl">
+ <tr><th>Video interface</th>
+ <td>Poorly engineered video interfaces (and/or their device drivers) can
+ "steal" computer resources for a long time, preventing the audio interface
+ from keeping up with the flow of data.</td></tr>
+ <tr><th>Wireless interface</th>
+ <td>Poorly engineered wireless networking interfaces (and/or their device
+ drivers) can also block the audio interface from keeping up with the flow of
+ data.</td></tr>
+ <tr><th><abbr title="Universal Serial Bus">USB</abbr> ports</th>
+ <td>When using an audio interface connected via USB, and sometimes even if
+ not, the precise configuration of the system's USB ports can make a big
+ difference. There are many cases where plugging the interface into one port
+ will work, but using different USB port results in much worse performance.
+ This has been seen even on Apple systems.</td></tr>
+ <tr><th>Internal USB Hubs</th>
+ <td>Ideally, all USB ports should connect directly to the main bus inside the
+ computer. Some laptops (and possibly some desktop systems) come wired with an
+ internal USB hub between the ports and the system bus, which can then cause
+ problems for various kinds of external USB devices, including some models of
+ audio interfaces. It is very difficult to discover whether this is true or
+ not, without simply trying it out.</td></tr>
+ <tr><th><abbr title="Central Processing Unit">CPU</abbr> speed control</th>
+ <td>Handling audio with low latency requires that the processor keeps running
+ at its highest speed at all times. Many portable systems try to regulate
+ processor speed in order to save power—for low latency audio, this
+ should be totally disabled, either in the BIOS or at the OS level.</td></tr>
+ <tr><th>Excessive Interrupt Sharing</th>
+ <td>If the audio interface is forced by the computer to share an interrupt
+ line (basically a way to tell the CPU that something needs its attention)
+ with too many other (or wrong) devices, this can also prevent the audio
+ interface from keeping up with the flow of data. In laptops it is generally
+ impossible to do anything about this. In many desktop systems, it is possible
+ at the BIOS level to reassign interrupts to work around the problem.</td></tr>
+ <tr><th><abbr title="System Management Interrupt">SMI</abbr>s</th>
+ <td>SMIs are interrupts sent by the motherboard to tell the computer about
+ the state of various hardware. They cannot safely be disabled, and they can
+ take a relatively long time to process. It is better to have a motherboard
+ which never sends SMIs at all—this is also a requirement for realtime
+ stock trading systems, which have similar issues with latency.</td></tr>
+ <tr><th>Hyperthreading</th>
+ <td>This technology is becoming less common as actual multi-core CPUs become
+ the norm, but it still exists and is generally not good for realtime
+ performance. Sometimes this can be disabled in the BIOS, sometimes it cannot.
+ A processor that uses hyperthreading will be less stable in very low latency
+ situations than one without.</td></tr>
+ <tr><th>Excessive vibration</th>
+ <td>This doesn't affect the flow of data to or from the audio interface, but
+ it can cause the flow of data to and from disk storage to become
+ <em>much</em> slower. If a computer going to be used in an environment with
+ loud live sound (specifically, high bass volume), make sure it is placed so
+ that the disk is not subjected to noticeable vibration. The vibrations will
+ physically displace the read-write heads of disk, and the resulting errors
+ will force a retry of the reading from the disk. Retrying over and over
+ massively reduces the rate at which data can be read from the disk. Avoid
+ this.</td></tr>
+</table>
+<p>
+ Richard Ames presents a long (28
+ minute) <a href="https://www.youtube.com/watch?v=GUsLLEkswzE">video</a>
+ that is very helpful if you want to understand these issues in more
+ depth. It is a little bit Windows-centric, but the explanations to
+ all types of computers and operating systems.
+</p>