Linux Hardware Support

One of the most common questions asked by those thinking of using Linux, goes something like “Will it work on my hardware?” well there is not really a cut and dried answer to this one, you ask two Linux techs and you are likely to get three answers.

My answer is to this one is along the lines of “if you have a fairly recent machine, without anything too non-standard, then you have a good chance of it being Linux friendly”

For example if you have a white box PC with a generic motherboard, video card, etc then you are more than likely ok.

Anyway after so many years working with Linux on whitebox and branded hardware, both myself and several other contributors to this site have collected a large amount of information on the things to be aware of.

To make life less painful, I am not even going to try and cover every piece of hardware available, as to do that would be totally impractical and next to worthless, being out of date before more or less instantly.

So in place of this madness, covered here are classes of hardware rather than specific devices. For example I talk about each of the main sub-systems that make up both workstations and servers, then move onto common peripheral devices such as printers, video cards, modems and scanners.

DISCLAIMER: All the information contained in this page, or any linked from it, is provided as is, having no warranty or support of any kind, and is used entirely at your own risk.

Motherboards	Processors	Memory	Hard Disks
Tape Drives	Networking	Video Cards	Sound Cards
Video Capture	Optical Disks	Scanners	Modems (PSTN)

Motherboards

After so many years working with both Linux (and other *nixs), I can count the number of motherboards with problems on the fingers of one hand.

The only issues I have come across have been with boards which I class as just plain odd, things like Apricot Zen machines, some specialist Japanese machines, and some of the early embedded boards.

Over the past few years I have actually seen no issues with any of the generic boards of the types usually used in whitebox machines, which have come across my desk.

As a general rule of thumb I would say that if you have anything that falls into the following categories you should be OK.

• Generic whitebox PC (just about anything recent)
• Branded (IBM, Dell, Gateway, Sony, Fujitsu, Toshiba etc)
• SUN Sparc (Sparc 1,2,5,10,20 etc)
• Newer Apple (G3, G4, G5 etc)

1. Some motherboards come with integrated IDE/SATA raid controllers, which are really designed for windoze only. Well all is not lost, some of these can be made to work with Linux, for example my PVR machines motherboard has one of these things based on a “promise technologies” chip, which works well, with 2.6.12 or later kernels. More on this later…
   
   
2. I have had several reports that some of the newer motherboards used by HP/Compaq are designed for nothing but Windoze, and have serious compatibility issues with Linux. As of yet I have not personally seen these things, so cannot confirm the nature of any problems or even if these reports are true, but if its anything like the old Compaq laptops that would not even run DOS, then anythings possible.
   
   
3. One new addition to the supported motherboards are some of the newer server boards which use hot plug PCI technology, although you need to be using one of the latest kernels to fully take advantage of this technology.

Processors

The brain of your machine, and yet another that I have come across next to no issues with Linux support. My personal experience covers:

• Intel 80386, 80486, Pentium, Pentium 2, Pentium 3, Pentium 4, Xeons, Pentium 4 with hyper threading, Dual core Pentium 4.
• AMD K6, K7, Athlon x2, Athlon 64
• Transmetta Crusoe
• Sun Sparc
• Power PC G3, G4 and G5

The only issues I am aware of, although have no personal experience are with the use of the older IBM x86 clones that date from the 80486 days, and the Cyrix family of x86 clones.

The problems are mainly to do with the stability and memory handling of these chips, and indeed I have had major problems with Cyrix under various versions of Windoze, so be warned.

Here is a good place to cover multiprocessor SMP (symmetric Multi Processing) systems, which are supported, but you are strongly recommended to use the 2.6 series kernels, which provide excellent support, and are a vast improvement over the older 2.2 and 2.4 kernels where the support was less than ideal.

My personal experience with SMP is limited to a maximum of 2 CPUs (Pentium, Pentium 2, Xeon and Hyper threading P4’s), and with these machines I have had no issues what so ever. I have even had a report of Linux with the 2.4 Kernel being successfully used on an Apple Dual G4 Power Mac machine.

Another recent report, talks about Linux running on one of the excellent Apple quad core G5 Powermacs. The report was a little thin in detail, but did talk about all things working well using the 2.6.10 kernel, and that the 8GB of memory the machine had being fully supported.

Now I actually have one of these quad core G5 machines, so could try it myself, assuming I actually get the time to play around with Linux on this machine. Anyway if I get the chance expect a full report of Linux on this machine.

1. Hyperthreading on Intel P4 class chips is supported by the 2.6 Kernels, its seen as two CPU. Just be aware some pre-built kernels may not offer full support, you may need to use a SMP kernel, or even compile your own to guarantee full support.

Memory

I have had some reports of issues with detecting the full amount of memory in some laptops, servers and workstations, specifically with older Compaq Proliant, and some very old AST desktops. This may sound bad, but in reality its very minor and easily fixed by setting the amount of memory manually, which from personal experience has no ill effects what so ever.

One thing to note, for those who have systems with more then 4GB of memory, your pre-built distribution kernel may not see past 4GB. To make this go away you will need to compile your own kernel, or at the very least consult your distribution documentation for alternative pre-built kernels to use.

1. I have not seen any sign of this issue in years, so it’s not something I would really worry about. It’s included here, to help those working with ancient hardware.
2. As far as I am aware this memory size detection issue only affects the old 2.2 kernels. If you know different please let me know

Hard Disks

I have never seen any Linux Hard disk issues other than those related to the controller, rather than the physical disk itself, which is why this section does not cover the actual disks, instead it just covers the two most popular controller type, SCSI and IDE, plus their RAID versions.

• SCSI. Linux supports ISA, PCI, PCIx, some EISA and MCA SCSI controller cards from the major manufactures, plus a smaller selection of less common cards from less well-known manufactures. Over years the majority of cards I have come across are made by Adaptec and Symbios logic, both are well supported by Linux.
  
  The majority of my experience, is with Adaptec cards based on the AIC788x chipset which covers the popular 294x series cards, which brings me to the only real issue I have ever experienced, which is with the automatic SCSI termination some of these cards feature.
  
  The actual nature of the problem is that the card has problems correctly setting the SCSI bus termination, which causes real strange issue with any devices (not just disks) attached to the bus.
  
  OK this is not really a Linux issue, but is still worth covering, as its been used as an excuse to use Windoze over Linux by some people, regardless of the fact that Windoze also is affected with this problem.
  
  As for the Symbios logic cards, my personal experience is limited, so all I can really say is that I have so far had no problems with these things, although I have found them to be slower then the Adaptec cards under Linux. In some cases based on the end use I would recommend replacement with an Adaptec card, for example if the card was being used to control a disk, I would replace it every time, whereas if its going to be used for another device such as a tape drive or scanners, I would normally keep it.
  
  
• SCSI RAID. You will usually find this type of card in high-end servers, and from time to time, they can be found in all sorts of places, from the very low-end server, to workstations (one of mine for instance).
  
  They can be the cause of some real pain, interesting installation and configuration or even in some cases terminal problems with Linux. Now before you get worried, I need to qualify this.
  
  There are two main types of these controllers, one cause nothing but pain and suffering, while the other is better supported and causes few if any problems. To make things clearer each are covered below.
  
  
  • Dedicated cards. These are the most common type of RAID controller I see in servers, plus the odd workstation, they are usually a single card, which contains a processor, memory, and one or more SCSI controllers. My personal experience with things has been with cards from; IBM, Compaq, Dell, PSI, Adaptec, AMI plus all sorts of OEM cards (usually AMI based), all have been supported by Linux with out any major issues.
    
    One word of warning, the installation of Linux on systems with some of the newer Adaptec and Compaq cards can be a little complex, but in the they are worth the effort as the performance and stability under Linux in general is excellent.
    
    
  • Add-on cards. To me these things should not really be called RAID controllers. What they actually are is a card that works with existing SCSI controllers (usually integrated onto the motherboard), to provide what I call a pseudo RAID.
    
    Now for the bad news, if you find you have one of these things, you have a problem as although some of these things claim to be supported with the 2.6 kernels, I have not tried it personally, and so far have not had any positive reports from those who have.
    
    So far I have only come across these things in workstations and one server, which was replaced with a new card, so Linux could be used.
    
    So use these things only if you really know what you are doing, and have time to really dive into the configuration.
• IDE. These days, there are two types of these things in mainstream use, the first, PATA is the oldest and finally starting to die out, being replaced with the second SATA. Both are well supported under Linux, although you really need to use the 2.6 kernels with the newer SATA drives.
  
  From personal experience, using the 2.6 kernels, neither PATA/SATA have given me any real problems. The only issues I have come across where actually nothing to do with the actual drive or even the interface, but where nothing more complex than BIOS settings.
  
  These days when building a Linux box, SATA drives are all I will use, if for no other reason that the wiring is easier. And yes the performance is, in most cases better than the older PATA drives.
  
  
• IDE Raid. There are several types of IDE raid controllers, with the most common being integrated onto just about every motherboard made in the past few years.
  
  Then comes the second and much less common, these things are what I call “true raid” and just like there SCSI big brothers usually contain a processor and memory, taking the whole task of controlling the disks away from the system CPU.
  
  Both of these types of controllers have their positive and negative points, which really need to be taken into account when deciding which to use.
  
  
  • Integrated. These things as I said above are usually integrated onto the motherboard, but not always, as yes you can get one separately for machines that lack this functionality.
    
    Anyway, the story with these things and Linux is improving with every new kernel update. At the time of writing, they are generally supported, although you are strongly advised to use the latest 2.6 kernel available.
    
    Now for the words of warning: these things can be interesting to downright painful to setup with Linux, as most work via the drive mapper interface which is not exactly well documented.
    
    So expect to jump through hoops before you get it working, especially if it’s going to be your boot device.
    
    I have setup a large array of drives using the integrated controller on my ASUS P4C800E motherboard that, in this case is powered by one of the Promise FastTrak 378 chips.
    
    While my experience is limited to promise chips, others do claim to be supported, I just have no reports either way as to if they actually work or not.
    
    If you want to try one, I suggest you check out the kernel documentation for the current list of supported controller chip sets.
    
    
  • Dedicated cards. These things are available, although are very rare, such that I have only ever seen one in the past few years, which if you look at the price, is very much understandable.
    
    Anyway, the Linux support for these things is a little patchy, with the only reports that have come my way being to do with the Adaptec 2400A, which is not exactly current technology.
    
    So if you are considering using one, I would suggest, just as with the integrated controllers, check out the kernel documentation to see what’s supported.
    
    

TIPS: Before moving on their are a few things that I feel worth while mentioning as they have caused me problems in the past.

1. With Adaptec SCSI Cards you need to disable the automatic termination, setting it manually. This will save you many hours to days of diagnosing problems that are right out of the twilight zone. Also as I mentioned above, this issue has been used by some people as a excuse to use Windoze over Linux, which is nothing short of propaganda as this issue affects all operating systems equally, not just Linux.
   
   
2. With the newer Adaptec RAID cards, you need the very latest firmware and drivers or the controller memory size is not always detected correctly.
   
   
3. With the AMI Mega-raid driver, DO NOT USE the driver from the AMI web site, it caused me real pain, the driver under Kernel 2.4.16 or later is much better. NB. Dell and HP use these cards in older servers, under the mega-raid and perc brands.
   
   
4. Future domain SCSI cards, are not recommended. Every one I have come across, while supported, has performance issues and is better off being replaced especially if they are used for disk control, other uses such as tape, CD etc may be acceptable, but I would still replace it, if at all possible.
   
   

Tape Drives

Of the many different types of tape drives available, the most common I see are SCSI DAT (DDS1 and DDS2) drives, which are well supported under Linux, as are some of the larger capacity drives such as DLT drives.

All of these drives are using some form of SCSI interface, so my comments about SCSI Controllers in the Hard Disk Section, are also valid here.

Non-SCSI. In the past, a non-scsi drive would usually mean one of those really nasty “floppy tape” drives, which as the name suggests use the legacy floppy drive interface.

Believe it or not, Linux does support some of these things, although I have never actually used one, various people who do tell me the support while it does exist is patchy, and less than wonderful.

So if you have one of these things I would check the kernel documentation before even thinking of trying to make it work with Linux.

These days you can get drives which use SATA, Firewire, USB and just about anything else you can think of.

• SATA. These things are very new, and so far I have yet to come across one in the real world.
  
  
• Firewire and USB. Both of these are external devices, and although I have no personal experience with them, reports that have come my way are all good, when it comes to support from Linux.
  
  
• Other. Things like parallel port tape drives, and other such abominations, well although someone someplace may have written a driver, I would avoid these things at all costs.
  
  As from dim and distant memory of their use under DOS and to a very limited extent very early windoze, they are next to useless even if they could be made to work.
  
  

Networking

Over the years, I have used cards from most of the major manufactures under Linux with no problems at all. For example with Ethernet, everything 3COM, Intel, Netgear, Linksys, SMC, DEC, IBM, or Broadcomm that I have ever come across just worked without any problems, although I do as always, recommend that newer kernels are used.

In addition to these Compaq Netflex cards are supported, as are some of the multiple port Ethernet cards from Intel and Adaptec. Just be warned some of these multi port cards can be complex to setup and use under Linux. As always check the kernel documentation to see the current driver status.

One thing that you really need to be aware of with network cards, is that you get what you pay for, so do not expect the same level of support from a $5 noname, as you get from a $40 3com or Intel card.

Sure they may work, but there is no guarantee of stability or that the driver if any, is maintained.

I have several reports from people having problems with really cheap cards. So my advice would be to spend the extra money and get something branded.

One thing that you really need to be aware of with network cards, is that you get what you pay for, so do not expect the same level of support from a $10 noname, as you get from a $40 branded. Sure they may work, but there is no guarantee of stability or that the driver if any, is maintained.

I have several reports from people having problems with really cheap cards. So my advice would be to spend the extra money and get something branded, just remember to check the kernel documentation for detailed compatibility help.

So far I have only covered Ethernet cards as they are the most common, but are not the only ones in use, others include; fibre and token ring. I have no personal experience with these types of card, under Linux, but others have reported that some cards from the major manufactures are supported.

Wireless

Some of these cards are supported under the 2.4 and later Kernels, but as expected the level of support is very much card chipset dependent, and varies widely.

I have used cards from Linksys, CISCO, and DLink under Linux with no real problems. The best support so far has been from CISCO, with cards based on the Prism2 chipset (Linksys, DLink and others) coming a close second thanks to the excellent support from the Linux-wlan project.

Other than these I have reports that Lucent and 3Com cards are also supported, but have no personal experience with these cards.

The only real problems I have had with these cards, has been with an "Avaya Gold Card" which has never worked well for me. Others have reported that these things do work, and suspect that I have a sick card, I am not convinced, after having the same problems with 3 different cards, but you never know.

TIP: OK so its a little out of place here, but there is one point thats worth mentioning, which is a fairly common problem with some 3COM Ethernet cards, that under windows do not auto detect the line speed correctly, well under Linux I have never seen this problem. Interesting yes?

Video Cards

With the sheer number of different cards in use from just as many vendors, it’s impossible to say with any real accuracy what’s supported and what’s not.

Some cards are well supported; others have some support, while others have zero support, with the level of support depending on any number of factors, for example;

• Chip set. Without going into too much specific detail, the mainstream video card market is more or less divided up between cards using Nvidia or ATI GPU chips.
  
  
  • Nvidia. Believe it or not, Nvidia does actually provide drivers to support some of cards using their GPU chips under Linux. The bad news is, these drivers are not open source, being supplied only in binary form.
    
    However from personal experience, I can confirm that the support for the 6x00 based cards is excellent, with all the functionality being available. And yes that does include dual monitor support.
    
    A big thumbs up to Nvidia for supporting Linux, and a wish that they would make open source drivers available in place of the current binary only ones.
    
    
  • ATI. Yes they also provide drivers for Linux, but unlike Nvidia I have no personal experience with their products, let alone their Linux drivers.
    
    
  And before I get any more emails, yes I know these two are not the only vendors in the GPU/Video card business, but they are the most popular.
  
  The only other well-known vendor that comes to mind with Linux driver support is Matrox. In the past I have use their cards with little to no problems, although I have no recent experience with these cards, I would not expect the level of support to have gone down.
  
  As always I recommend you check out the vendors web sites for more information about cards, GPUs, Linux support before making your own decision on which one to go for.
  
  While I think about it, you do not need to buy branded graphics cards, as most provide either OEM cards or chips to other companies. These other companies’ cards can in some cases be identical to the branded ones, just cheaper.
  
  
• Version of X windows you are using. With the more recent versions, the driver support is getting better; most of the newer cards are supported fairly well, as are many of the older cards. For more see the driver listing for specifics.
  
  On my PVR, I am using Xorg-X11 version 7, with the Nvidia 1.08756 drivers, which run without any issues with my Leadtek branded 6800U card.

TIP: For the Matrox cards, there is a open sourced driver on the Matrox web site, which I strongly recommend that you use to get the most out of your card.

1. If you are building a Linux server, then the choice of video card is about as simple as it gets. With Linux servers not needing any graphical interface, any card that supports 80x25 text display is more than enough.

Sound Cards

With the arrival of the 2.6 kernels, the preferred sound drivers changed to the alsa project. Not that in my case it made any difference as I have been using the alsa drivers, and nothing but for several years.

Anyway, the alsa drivers support an impressive collection of cards, all of which are listed on the alsa-project site, together with any available howtos specific to any of the cards.

From personal experience, I have had very little trouble with sound cards. Even with some of those integrated into older laptops, can be made to work with little effort.

I do how ever recommend that you checkout the supported cards lists, before buying a new card.

1. With just about all newer motherboards having integrated sound, Linux drivers are not usually any issue. With many of these boards (including all of mine) using integrated AC97 which is 100% supported by the alsa drivers.
   
   Other motherboards may use something else, so as always you are recommended to check the alsa supported cards list for help getting Linux running.

Video Capture

Just as with video cards, the number of different cards available makes it impossible for me to cover all of them. In place of this I will cover the two main kinds, which are "TV Tuner/Capture" and "Integrated Video/Capture cards".

Under Linux there is a standard for supporting video capture cards, which is "Video 4 Linux", which makes life easy for developers to support video capture devices, providing the cards driver conforms to this.

• TV Tuner cards. There are two main types of cards in use today; these are the older analogue tuners and the newer digital ones.
  
  The Linux support for both types used to be a little patchy, but things have changed, with the analogue cards being well supported, provided they are based on one of the common chipsets, such as the brooktree BTxxx chip.
  
  Cards based on this specific chipset are very well supported, and from personal experience require little in the way of configuration. The driver supplied with the kernel source is all that’s needed, and provides full video4linux support, which put simply means just about any application that supports this standard, should work.
  
  This specific chip set is used on many of the generic unbranded TV cards, and also with some of the Hauppauge WinTV cards.
  
  NB. The newer Hauppauge PVR cards do not use this chipset, but are supported by other drivers. More on this later...
  
  Now this is not the only chipset supported, some of the newer ones, which replace the BTxxx ones, are also supported.
  
  I have no personal experience with these things so cannot really comment on the level or quality of the drivers, all I can say is no one has reported anything bad.
  
  Now comes the digital cards, and here also the news is good, with Linux support being available for the more common cards. For example Vision Plus and Dvico cards are well supported.
  
  Just as with the analogue cards, digital support is dependent on the specific chipset used on the card. For example, my Dvico dual tuner card is based on the “Conexant CX23880” chip, which is well supported.
  
  Anyway, as always before buying any card, check the kernel documentation for compatibility.
  
  

TIP: Regardless of the card you running with, you really want to use the driver as a Kernel Module, unless you like having to reboot when the driver is taken out by a badly behaved application.

Optical Disks

This class of device includes, CDROM, DVD, DVD-R(RW), CD/DVD/CDRW drives. There is all good news on the Linux support front, in that every IDE or SCSI drive that I have ever seen has been fully is supported under Linux. And it gets better, as even some of the ancient drives that ran from a special controller or sound card are supported, although these will not boot CDs.

• CD Writers. IDE, SCSI, Firewire and USB drives are in general supported, although you need to check the list of supported drives on the cdrecord web site.
  
  
• DVD Writers. Just as with the CD writers, the support for these drives is excellent. My personal experience is mainly with Pioneer, Matshita and Aopen drives, all of which have given zero problems.

1. While I have not seen any issues with DVD writers, the same cannot be said about the media. So far of all the media used, the laser branded proved to be the worse of the lot.
   
   In late 2005, I was getting a failure rate of over 40%, spread across my Linux and Apple machines.
   
   After that nightmare failure rate, I now use mainly unbranded generic media, and the failure rate has dropped down to next to nothing.
   
   
2. Before anyone else emails me, at the time of writing, I have no information either way, with regard to support for dual layer support under linux. However I would expect the drive to be supported, just not sure about the actual writing software support.

Scanners

Just as with video cards, hard disks and sound cards, the number of different scanners available makes covering them all impossible, so in-place of even trying that I will cover the main different interface types, which are: SCSI, USB, Firewire and Parallel.

• SCSI assuming that your SCSI controller card is supported, I have not seen any issues with supporting this class of scanner. See my discussion on SCSI controllers for help with SCSI controller support.
  
  
• USB While I have no personal experience with these things, it does seem that many are supported. I would recommend you check the software supported scanner list before even trying to make any specific scanner work under Linux.
  
  
• Firewire I have no personal experience with these things, just as with the USB scanners, it does seem that some are supported.
  
  
• Parallel As far as I am aware there is minimal to zero support for these things. I had a report that there was an open source project on sourceforge started to write a driver, but I have not been able to find out anything more. So I would recommend that you assume that Parallel port scanners are not supported.

Software, well the final words on scanner support and Linux, are all down to the software. Anyway, while there are several open sourced scanner support applications available, I went the closed source path, and opted for vuescan to run my SCSI film scanner with Linux.

Without ending up writing a review here, there is really nothing bad that can be said about vuescan, it simply just works, and for the price, cannot be beaten.

That said, check out the vuescan web site, which has a very comprehensive list of supported scanners, and not just under Linux, under all platforms vuescan runs with.

NOTE: I have extensive experience using Vuescan with my Polaroid Sprintscan 4000 film scanner, and would recommend that you use this software over all others under Linux, even though its not open sourced, the expense is small and well worth it.

Modems (PSTN)

Modem support is dependent on the type of modem that you own, there are three main types of modem, which are: Winmodems, Serial Modems and USB. Each are covered below.

• WinModems. These things are a total abomination; they are designed to work only under Windoze, and actually use the systems CPU via a special device driver, to in effect emulate a modems functionality. Nasty right? Well believe it or not there is some very limited Linux support for some specific WinModems, although this is usually only available for laptops. My recommendation is to replace any WinModems with something that’s better supported.
  
  
• Serial. These are what I call a "Real Modem" and are available as external or internal models, from a variety of manufactures. They are in general well supported, with the exception of some of the very latest low-end models, which are really WinModems. If unsure if you have one of the new nasty WinModems, you need to talk to your modems manufacturer to confirm what you actually have. In general modems older than a few years are likely to be OK, but still check it out before buying.
  
  
• USB. These are the latest form of modem, and are the result of the move within in the industry to remove what are known as legacy ports from all new machines. The serial port is a legacy port, as is the good old parallel printer port. With Linux support I have no personal experience or even any reports from Linux users over compatibility, so cannot really comment, other than to say there is some 2.4/2.6 kernel support available.

Yes I know with the explosive growth in the use of broadband Internet access, the use of the older analogue modems is on the decline, but until they die out totally, there is very much still a need to cover these things with Linux.

Laptops

Linux is supported by many Laptops, but be warned there are many gotchas just waiting to bite you with some specific machines. So just like with the desktops and servers, I will cover generic laptop components.

• Keyboard. No real problems here, with the exception of some laptops that have Windoze specific keys which in some cases cannot be used for anything. Some laptops also have special purpose keys, for things like playing CDs, taking still images (Sony Vaio Picturebook) etc. Now all is not lost, in some cases there are actually drivers available that allow these buttons to be used, a good example of this is the capture button on the Picturebook which is supported by the SonyPI driver, which also runs the inbuilt video camera.
  
  
• Video. Just as with non-laptops, the level of Linux support depends on the video card (the chipset!) thats used in the specific model of laptop. These days it seems that ATI and Nvidia are the two most common, which is good news as the support from Xfree86 is good for both of these, plus there is actually some support from ATI and Nvidia, which is always a good thing to see. As always you are recommended to check the supported cards lists at the Xfree86 web site before even thinking of Linux on a laptop.
  
  
• Hard Disks. All laptops use IDE, usually PATA, disks that are supported out of the box by Linux without any issues.
  
  
• Mouse/Pointers. Again more good news, with the vast majority of laptops using the IBM/Toshiba style trackpoint or the cheaper touch pad (yuk!) type of pointing device. Both of these are treated as a mouse under X window, and in some cases any extra buttons, scroll wheels etc are also supported. The only problems that I have ever heard about with these things are on laptops that have both these pointing devices and do not provide a way to disable on or the other in the BIOS, in which case while Linux will run, both are active at the same time, which will drive you nuts. Sorry, but I am not aware of a fix for this one as yet.
  
  
• Ports. These days laptops are commonly coming with all sorts of odd ports some that I have experience with are:
  • USB 1.x. Ports that are compliant with the UHCI standard are supported.
    
    
  • USB 2.x. My experience with USB 2 ports and devices has been all with desktop systems. That said so far I have had no issues with any fairly recent USB 2 controller, but do recommend you use the most recent kernel available.
    
    
  • Firewire/IEEE1394/iLink. So far I have not seen any of these things that is not Linux compatible, and can confirm the ports Sony provides on the Vaio laptops is supported well.
    
    
  • Legacy Ports. These include classics like, parallel printer, serial and joystick etc, and in general are all supported.
    
    
  • Video Out. See my notes above in the Video Card section for this one.
    
    
• Network. The level of Linux support for integrated NICs varies from machine to machine, and is determined by the chipset used to power the network port. Some of the common ones are; 3Com and PCnet, both of which are supported.
  
  
• PCMCIA. No real problems with using PCMCIA cards. Under the 2.4 kernels there is good mature support for both 16bit and cardbus cards on most laptops. Some of the types of cards I have personally tested are: Network, Modem, SCSI, Firewire and USB, all of which where supported.

  NOTE: See my notes on the dreaded WinModem in the Modems section, as some PCMCIA modem cards are actually these things.
  Also understand that Linux support for specific cards, varies from zero to excellent, so before buying any new cards, you are strongly recommended to check your distributions hardware compatibility list.

• Optical Disks. Just as with the hard disks, all laptops that actually have some form of optical disk, use IDE drives which are supported. Its been reported that even the CD writer function on CD/CDRW and DVD-R combo drives are supported.
  
  
• Infra Red. I have no personal experience using infra red ports under any laptops, as none of my laptops actually have one of these ports, and also I have nothing to test with. All I can say is that under the 2.4 kernels there is support available, and others have reported success under Linux.
  
  
• Sound. This is treated just the same as non-laptops.
  
  
• Power Management. This one is very dependent on the specific laptop, and is the one area where there are real problems with Linux support on some systems. Usually these problems are on laptops which use the ACPI standard over the more mature APM BIOS. The problem is that Linux ACPI support is very much work in progress, with things like suspend/resume not being functional. For full ACPI support, its looking like the upcoming 2.6 kernel will be the first to offer full ACPI support.
  
  
• Modems. This is another problem area, and actually worse than the modem problems with non-laptops, in that every modem I have ever seen or heard about thats integrated into a laptop is a WinModem, and so suffers from minimal Linux support at best. Worse than that there seems to be a ever increasing trend with PCMCIA modems to also be WinModems (all in the name of saving $$$ and keeping the beast happy). So assume that your integrated modem is a WinModem, and check out the linmodems site for what support there may be. With PCMCIA modems check with the manufacturer as to the nature of the modem, if its not a WinModem then its going to be some form of serial modem which should be supported by Linux without the need for any special drivers.