[lug] external monitor question

[Davide Del Vento]

Sorry for the follow up, but forget an important detail: the monitor
is flat panel LCD and *not* CRT, so I was not expecting to see this
behavior.
Thanks,
Davide

On Sun, Nov 6, 2011 at 14:19, Davide Del Vento
<davide.del.vento at gmail.com> wrote:
> Hi,
> I'm trying to connect a Dell 19" monitor (bought in the USA) to an old
> Dell inspiron 6400 Laptop (bought in Europe) with a VGA (analog)
> cable. This is under Ubuntu 10.04
> The laptop correctly sees the monitor and identify 1280x1024 as the
> best setting, but on that setting the monitor display the image with
> "waves" on the vertical axis. The monitor diagnostic also says that
> this mode is a 58Hz or 59Hz signal (it does not always say the same).
> The laptop thinks it's 60Hz.
>
> Playing with gtf and xrandr, I can modify the frequency (and maybe
> even the intensity) of the waves from "very annoying" to "disturbing"
> to "cool" to even "funny". But it never goes away (I haven't tried all
> possibilities yet, though). On some modes (e.g. 63Hz) the monitor says
> "Cannot display this video mode" which is strange since it can display
> the 62 and 64Hz (by the way, the 64Hz are 64Hz for both the laptop and
> the monitor).
>
> The question: do you think this is hopeless and I should give up
> (given the 60hz vs 50Hz of the power line in Europe vs USA), or do you
> think that I should eventually be able to find a non "waving" mode?
> Ah, I also tried on laptop battery instead of power brick, FWIW.
>
> Thanks,
> Davide
>