Subject: Re: Pixelclock too high
To: None <port-amiga@netbsd.org>
From: Bernd Sieker <bsieker@freenet.de>
List: port-amiga
Date: 06/29/2000 13:07:07
On 29.06.00, 08:36:03, Georges Heinesch wrote:
> Quoting Bernd Ernesti (28-Jun-00 09:50:16):
> 
> > This are the chip limits, so even CV_AGGRESSIVE_TIMING is 25% over
> > the limit for the 16bit mode.
> 
> Do I harm the CV64 in any respect (hardware wise) when I use modes
> which go above this 25% increase limit? I can use these modi under
> AmigaOS without any problem.

Potentially you may harm it if you go only a little bit over the
limit, that's why there is a limit, after all.

The Trio64 Chips as used on the CV64 (not CV643D) are known to work
quite well even if overclocked, that's why "CV_AGGRESSIVE_TIMING" is
available.

However, the 25% limit, too, seems rather arbitrary, and I think it
should be at anyone's own risk, if he wishes to push the pixel clock
even farther up.

So maybe (a) "CV_AGGRESSIVE_TIMING" should allow more, or (b) there
should be another option, like "CV_REALLY_AGGRESSIVE_TIMING", which
might allow to exceed the limit by 40% or 50%.

> 
> > And your mode #12 is 37.5% over the chip limit.
> 
> And mode #13 is 35% above.
> 
> TIA
> 
> -- 
> Cu  Georges Heinesch, Luxembourg

-- 
Bernd Sieker

NetBSD logo: Kiss-painted (w/tongue) Beastie stabbing a pitchfork
       through a bloodied and obviously-in-horrible-pain Tux.
		-- Mason Loring Bliss