[ltp] Re: X60 produces fuzzy VGA output in high resolutions - will Ultrabase help?

Henrique de Moraes Holschuh linux-thinkpad@linux-thinkpad.org
Wed, 8 Apr 2009 11:39:14 -0300


On Wed, 08 Apr 2009, Marius Gedminas wrote:
> On Tue, Apr 07, 2009 at 10:31:13AM -0400, Stefan Monnier wrote:
> > > rate the quality is quite good, but if I go all the way to 1680×1050 px
> > > the refresh rate drops to 60 Hz (or maybe 50 Hz, I can?t check at the
> > > moment) and my external screen looks a bit fuzzy, much worse than the
> > 
> > Do you know why the refresh rate drops?  I was running a 1800x1400
> > screen at 70Hz with a measly Matrox Millenium ten years ago, so I'm
> > pretty sure the X60 is able to provide higher refresh rates.
> 
> I expect LCD monitors do not advertise modes with higher refresh rates
> in their EDID info.

The bandwidth is limited, as you increase resolution, you have to drop the
refresh rate to keep within the limited bandwidth.

This is far worse on DVI than VGA as far as the connection goes, but the
monitor and GPU themselves have output bandwidth limitations (maximum pixel
clock, etc).

-- 
  "One disk to rule them all, One disk to find them. One disk to bring
  them all and in the darkness grind them. In the Land of Redmond
  where the shadows lie." -- The Silicon Valley Tarot
  Henrique Holschuh