ca/hardware/supported-peripherals.xml

<!-- retain these comments for translator revision tracking -->
<!-- original version: 28672 untranslated -->

 <sect1 id="supported-peripherals">
 <title>Peripherals and Other Hardware</title>
<para arch="not-s390">

Linux supports a large variety of hardware devices such as mice,
printers, scanners, PCMCIA and USB devices.  However, most of these
devices are not required while installing the system.

</para><para arch="i386">

USB hardware generally works fine, only some
USB keyboards may require additional configuration
(see <xref linkend="usb-keyboard-config"/>).

</para><para arch="i386">

Again, see the
<ulink url="&url-hardware-howto;">Linux Hardware Compatibility HOWTO</ulink>
to determine whether your specific hardware is supported by Linux.

</para><para arch="s390">

Package installations from XPRAM and tape are not supported by this
system.  All packages that you want to install need to be available on a
DASD or over the network using NFS, HTTP or FTP.

</para><para arch="mips">

The Broadcom BCM91250A evaluation board offers standard 3.3v 32 bit and 64
bit PCI slots as well as USB connectors.

</para><para arch="mipsel">

The Broadcom BCM91250A evaluation board offers standard 3.3v 32 bit and 64
bit PCI slots as well as USB connectors.  The Cobalt RaQ has no support for
additional devices but the Qube has one PCI slot.

</para>
</sect1>

 <sect1 arch="not-s390"><title>Purchasing Hardware Specifically for GNU/Linux</title>

<para>

There are several vendors, who ship systems with Debian or other
distributions of GNU/Linux
<ulink url="&url-pre-installed;">pre-installed</ulink>. You might pay more
for the privilege, but it does buy a level of peace of mind, since you can
be sure that the hardware is well-supported by GNU/Linux.

</para><para arch="m68k">

Unfortunately, it's quite rare to find any vendor shipping
new &arch-title; machines at all.

</para><para arch="i386">

If you do have to buy a machine with Windows bundled, carefully read
the software license that comes with Windows; you may be able to
reject the license and obtain a rebate from your vendor.  See
<ulink url="&url-windows-refund;"></ulink> for complete details.

</para><para>

Whether or not you are purchasing a system with Linux bundled, or even
a used system, it is still important to check that your hardware is
supported by the Linux kernel.  Check if your hardware is listed in
the references found above.  Let your salesperson (if any) know that
you're shopping for a Linux system.  Support Linux-friendly hardware
vendors.

</para>

  <sect2><title>Avoid Proprietary or Closed Hardware</title>
<para>

Some hardware manufacturers simply won't tell us how to write drivers
for their hardware. Others won't allow us access to the documentation
without a non-disclosure agreement that would prevent us from
releasing the Linux source code.

</para><para arch="m68k">

Another example is the proprietary hardware in the older
Macintosh line. In fact, no specifications or documentation have ever
been released for any Macintosh hardware, most notably the ADB
controller (used by the mouse and keyboard), the floppy controller,
and all acceleration and CLUT manipulation of the video hardware
(though we do now support CLUT manipulation on nearly all internal
video chips).  In a nutshell, this explains why the Macintosh Linux
port lags behind other Linux ports.

</para><para>

Since we haven't been granted access to the documentation on these
devices, they simply won't work under Linux. You can help by asking
the manufacturers of such hardware to release the documentation. If
enough people ask, they will realize that the free software community
is an important market.

</para>
</sect2>


  <sect2 arch="i386"><title>Windows-specific Hardware</title>
<para>

A disturbing trend is the proliferation of Windows-specific modems and
printers. In some cases these are specially designed to be operated by
the Microsoft Windows operating system and bear the legend
``WinModem'' or ``Made especially for Windows-based computers''. This
is generally done by removing the embedded processors of the hardware
and shifting the work they do over to a Windows driver that is run by
your computer's main CPU. This strategy makes the hardware less
expensive, but the savings are often <emphasis>not</emphasis> passed on to the
user and this hardware may even be more expensive than equivalent
devices that retain their embedded intelligence.

</para><para>

You should avoid Windows-specific hardware for two reasons. The first
is that the manufacturers do not generally make the resources
available to write a Linux driver. Generally, the hardware and
software interface to the device is proprietary, and documentation is
not available without a non-disclosure agreement, if it is available
at all. This precludes its being used for free software, since free
software writers disclose the source code of their programs. The
second reason is that when devices like these have had their embedded
processors removed, the operating system must perform the work of the
embedded processors, often at <emphasis>real-time</emphasis> priority,
and thus the CPU is not available to run your programs while it is
driving these devices. Since the typical Windows user does not
multi-process as intensively as a Linux user, the manufacturers hope
that the Windows user simply won't notice the burden this hardware
places on their CPU.  However, any multi-processing operating system,
even Windows 2000 or XP, suffers from degraded performance when
peripheral manufacturers skimp on the embedded processing power of
their hardware.

</para><para>

You can help this situation by encouraging these manufacturers to
release the documentation and other resources necessary for us to
program their hardware, but the best strategy is simply to avoid this
sort of hardware until it is listed as working in the
<ulink url="&url-hardware-howto;">Linux Hardware Compatibility HOWTO</ulink>.

</para>
</sect2>


  <sect2 id="Parity-RAM">
  <title>Fake or <quote>Virtual</quote> Parity RAM</title>
<para>

If you ask for Parity RAM in a computer store, you'll probably get
<emphasis>virtual parity</emphasis> memory modules instead of
<emphasis>true parity</emphasis> ones. Virtual parity SIMMs can often
(but not always) be distinguished because they only have one more chip
than an equivalent non-parity SIMM, and that one extra chip is smaller
than all the others. Virtual-parity SIMMs work exactly like non-parity
memory.  They can't tell you when you have a single-bit RAM error the
way true-parity SIMMs do in a motherboard that implements
parity. Don't ever pay more for a virtual-parity SIMM than a
non-parity one. Do expect to pay a little more for true-parity SIMMs,
because you are actually buying one extra bit of memory for every 8
bits.

</para><para>

If you want complete information on &arch-title; RAM issues, and what
is the best RAM to buy, see the
<ulink url="&url-pc-hw-faq;">PC Hardware FAQ</ulink>.

</para><para arch="alpha">

Most, if not all, Alpha systems require true-parity RAM.

</para>

  </sect2>

 </sect1>
1	<!-- retain these comments for translator revision tracking -->
2	<!-- original version: 28672 untranslated -->
3
4	<sect1 id="supported-peripherals">
5	<title>Peripherals and Other Hardware</title>
6	<para arch="not-s390">
7
8	Linux supports a large variety of hardware devices such as mice,
9	printers, scanners, PCMCIA and USB devices. However, most of these
10	devices are not required while installing the system.
11
12	</para><para arch="i386">
13
14	USB hardware generally works fine, only some
15	USB keyboards may require additional configuration
16	(see <xref linkend="usb-keyboard-config"/>).
17
18	</para><para arch="i386">
19
20	Again, see the
21	<ulink url="&url-hardware-howto;">Linux Hardware Compatibility HOWTO</ulink>
22	to determine whether your specific hardware is supported by Linux.
23
24	</para><para arch="s390">
25
26	Package installations from XPRAM and tape are not supported by this
27	system. All packages that you want to install need to be available on a
28	DASD or over the network using NFS, HTTP or FTP.
29
30	</para><para arch="mips">
31
32	The Broadcom BCM91250A evaluation board offers standard 3.3v 32 bit and 64
33	bit PCI slots as well as USB connectors.
34
35	</para><para arch="mipsel">
36
37	The Broadcom BCM91250A evaluation board offers standard 3.3v 32 bit and 64
38	bit PCI slots as well as USB connectors. The Cobalt RaQ has no support for
39	additional devices but the Qube has one PCI slot.
40
41	</para>
42	</sect1>
43
44	<sect1 arch="not-s390"><title>Purchasing Hardware Specifically for GNU/Linux</title>
45
46	<para>
47
48	There are several vendors, who ship systems with Debian or other
49	distributions of GNU/Linux
50	<ulink url="&url-pre-installed;">pre-installed</ulink>. You might pay more
51	for the privilege, but it does buy a level of peace of mind, since you can
52	be sure that the hardware is well-supported by GNU/Linux.
53
54	</para><para arch="m68k">
55
56	Unfortunately, it's quite rare to find any vendor shipping
57	new &arch-title; machines at all.
58
59	</para><para arch="i386">
60
61	If you do have to buy a machine with Windows bundled, carefully read
62	the software license that comes with Windows; you may be able to
63	reject the license and obtain a rebate from your vendor. See
64	<ulink url="&url-windows-refund;"></ulink> for complete details.
65
66	</para><para>
67
68	Whether or not you are purchasing a system with Linux bundled, or even
69	a used system, it is still important to check that your hardware is
70	supported by the Linux kernel. Check if your hardware is listed in
71	the references found above. Let your salesperson (if any) know that
72	you're shopping for a Linux system. Support Linux-friendly hardware
73	vendors.
74
75	</para>
76
77	<sect2><title>Avoid Proprietary or Closed Hardware</title>
78	<para>
79
80	Some hardware manufacturers simply won't tell us how to write drivers
81	for their hardware. Others won't allow us access to the documentation
82	without a non-disclosure agreement that would prevent us from
83	releasing the Linux source code.
84
85	</para><para arch="m68k">
86
87	Another example is the proprietary hardware in the older
88	Macintosh line. In fact, no specifications or documentation have ever
89	been released for any Macintosh hardware, most notably the ADB
90	controller (used by the mouse and keyboard), the floppy controller,
91	and all acceleration and CLUT manipulation of the video hardware
92	(though we do now support CLUT manipulation on nearly all internal
93	video chips). In a nutshell, this explains why the Macintosh Linux
94	port lags behind other Linux ports.
95
96	</para><para>
97
98	Since we haven't been granted access to the documentation on these
99	devices, they simply won't work under Linux. You can help by asking
100	the manufacturers of such hardware to release the documentation. If
101	enough people ask, they will realize that the free software community
102	is an important market.
103
104	</para>
105	</sect2>
106
107
108	<sect2 arch="i386"><title>Windows-specific Hardware</title>
109	<para>
110
111	A disturbing trend is the proliferation of Windows-specific modems and
112	printers. In some cases these are specially designed to be operated by
113	the Microsoft Windows operating system and bear the legend
114	``WinModem'' or ``Made especially for Windows-based computers''. This
115	is generally done by removing the embedded processors of the hardware
116	and shifting the work they do over to a Windows driver that is run by
117	your computer's main CPU. This strategy makes the hardware less
118	expensive, but the savings are often <emphasis>not</emphasis> passed on to the
119	user and this hardware may even be more expensive than equivalent
120	devices that retain their embedded intelligence.
121
122	</para><para>
123
124	You should avoid Windows-specific hardware for two reasons. The first
125	is that the manufacturers do not generally make the resources
126	available to write a Linux driver. Generally, the hardware and
127	software interface to the device is proprietary, and documentation is
128	not available without a non-disclosure agreement, if it is available
129	at all. This precludes its being used for free software, since free
130	software writers disclose the source code of their programs. The
131	second reason is that when devices like these have had their embedded
132	processors removed, the operating system must perform the work of the
133	embedded processors, often at <emphasis>real-time</emphasis> priority,
134	and thus the CPU is not available to run your programs while it is
135	driving these devices. Since the typical Windows user does not
136	multi-process as intensively as a Linux user, the manufacturers hope
137	that the Windows user simply won't notice the burden this hardware
138	places on their CPU. However, any multi-processing operating system,
139	even Windows 2000 or XP, suffers from degraded performance when
140	peripheral manufacturers skimp on the embedded processing power of
141	their hardware.
142
143	</para><para>
144
145	You can help this situation by encouraging these manufacturers to
146	release the documentation and other resources necessary for us to
147	program their hardware, but the best strategy is simply to avoid this
148	sort of hardware until it is listed as working in the
149	<ulink url="&url-hardware-howto;">Linux Hardware Compatibility HOWTO</ulink>.
150
151	</para>
152	</sect2>
153
154
155	<sect2 id="Parity-RAM">
156	<title>Fake or <quote>Virtual</quote> Parity RAM</title>
157	<para>
158
159	If you ask for Parity RAM in a computer store, you'll probably get
160	<emphasis>virtual parity</emphasis> memory modules instead of
161	<emphasis>true parity</emphasis> ones. Virtual parity SIMMs can often
162	(but not always) be distinguished because they only have one more chip
163	than an equivalent non-parity SIMM, and that one extra chip is smaller
164	than all the others. Virtual-parity SIMMs work exactly like non-parity
165	memory. They can't tell you when you have a single-bit RAM error the
166	way true-parity SIMMs do in a motherboard that implements
167	parity. Don't ever pay more for a virtual-parity SIMM than a
168	non-parity one. Do expect to pay a little more for true-parity SIMMs,
169	because you are actually buying one extra bit of memory for every 8
170	bits.
171
172	</para><para>
173
174	If you want complete information on &arch-title; RAM issues, and what
175	is the best RAM to buy, see the
176	<ulink url="&url-pc-hw-faq;">PC Hardware FAQ</ulink>.
177
178	</para><para arch="alpha">
179
180	Most, if not all, Alpha systems require true-parity RAM.
181
182	</para>
183
184	</sect2>
185
186	</sect1>