http://maketecheasier.com/gather-hardware-information-in-linux/2011/05/12

lspci

This standard system utility will show you much of what you’ve got internally. Yes, the name of the command is a combination of ls, the standard command to list files, and PCI, the peripheral connection. Despite that, it doesn’t show only PCI devices and you can expect your results to include AGP and onboard components like your USB chipset.

It’s often helpful to pipe the results of lspci through grep, so that you can filter out just the parts you’re looking for. Use lspci -v or lspci -vv for additional output.

Pros: Built in to virtually any Linux OS, quick and easy, thorough output.
Cons: Somewhat limited in the types of devices it can display.

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hwinfo

While lspci does more than just PCI, it doesn’t tell you anything about your hard disks, CPU, USB devices, etc. If lspci can’t handle it, hwinfo probably can. This application performs a much more thorough scan to determine what bits you’ve got connected to your PC, and provides a LOT of info by default.
you can use --short to provide more concise output, and --devicetype to list a specific type of information.Some of the more useful device types include:

    bluetooth
    camera
    cdrom
    cpu
    disk
    gfxcard
    ide
    memory
    monitor
    netcard
    partition
    printer
    scanner
    scsi
    sound
    usb
    wlan

Pros: Extensive output, very large device type support

Cons: Requires root privileges on many systems. Also not included in many base Linux installs. It should, however, be in the standard repositories of most major distributions.

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lshw

This tool comes in two forms, a command line version and a GTK graphical front-end. Testing for this article showed it to be somewhat less comprehensive than hwinfo, but makes up for it with a useful GUI (lshw-gtk) and the ability to output the results to HTML/XML.
Pros: Graphical frontend, particularly useful output options.

Cons: Produces very little output without root access, and even with root it doesn’t match up to hwinfo in raw power.

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