Refresh rate issue

**Ryo_** · 10-22-2003, 01:33 PM

Hello.

I downloaded the latest Knoppix release (3.3 2003-09-24), and it runs fine.

But I have one issue: my monitor can do 1024x768, as the graphics card, but only in 87interlaced vertical refresh rate.

So I have to force 800x600 to see something for XFree, and still Knoppix during boot (and shutdown) uses 1024x768 with a bad refresh rate, thus everything appears 4 times and is pretty hard to read

.

What parameters should i give at boot time to fix those issues?
Or is there something to tweak somewhere?

TIA!

**Stephen** · 10-22-2003, 08:36 PM

Originally Posted by Ryo_

Hello.

I downloaded the latest Knoppix release (3.3 2003-09-24), and it runs fine.

But I have one issue: my monitor can do 1024x768, as the graphics card, but only in 87interlaced vertical refresh rate.

So I have to force 800x600 to see something for XFree, and still Knoppix during boot (and shutdown) uses 1024x768 with a bad refresh rate, thus everything appears 4 times and is pretty hard to read

.

What parameters should i give at boot time to fix those issues?
TIA!

Try knoppix xvrefresh=60 screen=1024x768 and you may want to use the proper xmodule cheat code on the line as well.
Or is there something to tweak somewhere?

**Ryo_** · 10-25-2003, 09:55 AM

Hum I tried vsync=60, no go.
I'll try xvrefresh next time.

The issue is that my monitor doesn't even do 60hz, it seems. Yes it's a crappy old one

I know it does 1026x768 with 87 interlaced mode. I remember some X windows parameter somewhere to tweak that.

Also, Knoppix itself, for its console, obviously uses 1024x768, even if you specify the screen resolution to be 800x600. Any way to fix that?

(and cheat codes don't help much, or i don't understand'em

)

**RockMumbles** · 10-25-2003, 05:01 PM

How big is your monitor? (I would try to find all of the specifications for your monitor.) What is the 87 you are referring to, is that the horizontal scan rate in kHz??

I have had some old monitors that wouldn't run 1024x768 with knoppix but I could do an install and get them to run at 1024x768, so I ran them at 800x600 with knoppix and started with knoppix screen=800x600.

Also if your monitor won't run at xvrefresh=60 don't use 60 use another number for the 60, a value your monitor will run at.

CheatCodes can be a necessary part of knoppix.

~rock

**Ryo_** · 10-25-2003, 06:10 PM

87 hz is vertical refresh rate.
800x600 mode works fine, but 1024x768 requires 87hz interlaced vertical refresh mode.
Else the screen is real garbage

**Ryo_** · 10-25-2003, 06:36 PM

Currently under Knoppix, screen 800x600
But the console (at startup, or when hitting ctrl-alt-f1) is obviously still in 1024x768, thus i can't really read it...

And I'd prefer to work in 1024 under xfree, too

Thanks for the help in any case.