Motherboards and Buses - Upgrading and Repairing PCs - page 207

or Sempron 100. Mini-ITX systems that use these processors can be used as multimedia
servers and small form factor PCs as well as for set-top boxes and computing appliances.
ThesizeoftheDTXandITXfamiliesofmotherboardsastheyrelatetoFlexATXisshown
in Table 4.5 .
Whereas the still-born ITX format was virtually the same as FlexATX in size (which is
probably why it was discontinued before any were sold), the Mini, Nano, and Pico-ITX
form factors are considerably smaller than FlexATX, as is the mini-DTX.
To take advantage of the smaller Mini-ITX format, several chassis makers have produced
small chassis to fit these boards. Most are the shape of a small cube, with one floppy and
one optical drive bay visible from the front. The layout of a typical Mini-ITX mother-
board, the ASRock M67M-ITX, is shown in Figure 4.19 . Nano-ITX and Pico-ITX can fit
into slimline (half-U) cases that can be used horizontally or vertically.
Mini-ITX motherboards can offer a full range of input-output ports. And, while designs
that use VIA processors typically feature soldered-in place processors and lack PCIe ex-
pansionslots,designsthatuseIntelorAMDprocessorssupportawiderangeofprocessors
and feature a PCIe slot. However, Mini-ITX and smaller motherboards in the family are
not suitable when you need a highly expandable system (most feature only one expan-
sion slot) or when you plan to use processors with more than 100W thermal design power
(TDP).
The smaller Nano-ITX and Pico-ITX motherboards use soldered-in-place low-power net-
book/embedded-class processors from VIA, Intel or AMD.
Note
The official site for ITX information is http://www.via.com.tw/en/products/embedded/ . The
site www.mini-itx.com is often mistaken for an official site, but it is actually a vendor that
specializes in ITX systems and component sales.
Proprietary Designs
Motherboards that are not one of the industry standard form factors, such as any of the
ATX, DTX, or ITX formats, are deemed proprietary or semiproprietary . Most people
purchasing PCs should avoid proprietary designs because they do not allow for a future
motherboard, power supply, or case upgrade, which limits future use and serviceability of
thesystem.ProprietarysystemsaredisposablePCsbecauseyoucanneitherupgradethem
nor easily repair them. The problem is that the proprietary parts often come only from
theoriginal system manufacturer,andtheyusually costmuchmorethanindustrystandard
parts. Therefore, after your proprietary system goes out of warranty, it is essentially no