Flip 3d AND KVM Switch

Discussion in 'Windows Vista General Discussion' started by Paul D, Aug 15, 2007.

  1. Paul D

    Paul D Guest

    Anyone know why Flip 3D will not work on my system if I an musing a KVM
    Switch? When using the Vista computer alone, it works fine.

    This is on a notebook using a desktop screen as an extended monitor.

    Will Flip 3D not work with an extended monitor, perhaps?


    Paul D.
    Paul D, Aug 15, 2007
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  2. Hi Paul,

    I'm not aware of any fundamental problem between KVM and Flip 3D. For what
    it's worth, I'm connected to an Avocent SwitchView 4SVDVI10, and the
    Control-Tab key combo for Flip 3D works fine for my machine. But there are a
    large number of variables:

    - what brand and model of KVM are you using?
    - PS/2 or USB?
    - DVI or VGA?
    - actively powered, or passive?
    - length of keyboad connection cable?
    - and so on ...

    The bottom line is that Microsoft does not officially support using KVMs
    with Windows. Inconceivable, you say? Well, read on ... Firstly, let me say
    I've been using various KVMs at home and at work for many years; I don't
    discourage anyone from running a KVM. Neither does Microsoft. But they do
    not "support" it, in the narrow sense. In other words, if you ring Microsoft
    PSS and say "my Vista PC doesn't work with my KVM" they'll say (basically),
    that's a shame, thanks for calling, have a nice day. Likewise, if you open a
    bug report with the Windows team, they'll say "that's a shame, thanks for
    letting us know, have a nice day". The reason is that there is no industry
    standard - de jure or de facto - for how KVMs work; and there are no
    standard KVM interfaces for interacting with an operating system. For USB
    keyboards, the KVM has to operate as a USB wire-protocol multiplexor - a
    facility which is not in fact described in any of the USB specifications
    (although that may change in future USB versions). For PS/2 keyboards it is
    even dodgier, since this is a set of analogue signals which needs to be
    multiplexed. There are many different implementations, down at the
    electrical level - in the absence of standards, KVM manufacturers have to
    each invent their own. When I chatted about this informally with a Microsoft
    guy, he told me the test matrix to provide formal verification of KVMs with
    Windows would be enormous - essentially, it's the Cartesian Product of all
    keyboards, mouses, monitors, graphics cards and KVMs on the market. It is
    simply impossible, to support such a scenario. But in practice, there are
    thousands of KVMs in use across the Redmond campus.

    Hopefully as KVMs become more widespread, some standards will start to
    emerge ... although the whole USB, DVI, HDMI thing is in a state of flux, if
    standards ever emerge they might be more around IP-based KVMs and devices,
    rather than the local-device protocols like USB.

    Over the years I have experimented with several brands and models -
    Avocent, Gefen, Aten, Comsol Adder, Belkin, and several "no-name" Taiwanese
    brands. As a rule of thumb, the brands I consider really reliable are
    Avocent and Adder, followed by the over-priced Gefen, and then Aten. Belkin
    was very *unreliable*, at least in their USB/DVI models. For all KVMs,
    actively powered is more reliable than passive powered. Sadly, analogue
    technologies seem more reliable over KVM than any digital ones: PS/2 still
    seems to "KVM" better than USB; but computers with PS/2 ports are getting
    had to find! Ditto, for VGA versus DVI; if a DVI connection loses the EDID
    then you are toast: reboot your entire array.

    If your specific model of KVM has an upgradeable firmware, check with the
    manufacturer's website and download the lastest firmware update. This has
    fixed several problems for me.

    Apart from that ... if Ctrl-Tab doesn't work on your KVM, you may be just
    out of luck. There are no easy diagnostics to trace a USB signal (cheapest
    USB sniffer I found is I think ~US$5K, DVI sniffers are astronomical -

    The other thing to test would be to connect your keyboard directly to the PC
    and verify that the KVM is, in fact, the diacritical factor. Maybe Flip 3D
    is broken for some other reason, eg video driver etc.

    Other folks may have better info for you; hope this helps a bit.
    Andrew McLaren, Aug 16, 2007
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  3. Paul D

    Lang Murphy Guest

    I'm running Vista Ultimate on a Dell laptop connected to an 8 port APW PS/2
    KVM and have no problem invoking Flip-3D.

    Lang Murphy, Aug 16, 2007
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