Dear all,

Today I was trying to configure MorphOS to run in 1600x1200. However, I'm experiencing a little problem. When I up the resolution from 1024x768 to 1280x1024 or 1600x1200, the image appears, and only little tuning of the pulse length and offset is necessary to center the screen.

However, I do get these nasty "ghosts" (icons, windows, etc., are "copied" around 50 pixels to the left). While these "ghosts" are barely visible, after some minutes you get REALLY tired eyes (yeah, I tried).

My settings are:
Declared screen: Viewsonic E75f (there is no Hyundai Q995)
Real screen: Hyundai Q995
Horizontal frequency: ~84 kHz
Vertical frequency: 64 Hz
Video card: Radeon 9250 128 MB

The screen is suppossed to support up to 1600x1200 @75Hz (F horiz= 30 - 96 kHz / Fvert = 50 - 150 Hz), and the KVM switch (Belkin Omniview E series) should support up to 2048x1536 @85Hz.

So I guess I must be screwing up something in the config, since I am actually using 1600x1200 with the same screen and KVM switch connected to my PC under Linux & Windoze (with a Radeon X700 Pro).

Any clues? I really would HATE being forced to content myself with 1024x768 (it reminds me too much of my VESA card days).

I'm not sure about the description, but is the problem that, a few rows of pixels at one edge go "over the edge" and are shown mirrored?

Maybe your monitor allows per-screenmode adjustments so, that you can alter the width so, that it fits... Also test other screenmodes of the same size from the list in screenmode editor. One of them might be exactly the same that your PC is using (that way KVM screen switching should be faster too, as the monitor doesn't have to re-adjust)

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No, it is not a positioning problem. The image is shown several times (once in the correct position, once some pixels to the left but in a lower intensity and so on). Just like you take the screen, copy it, give it a 50% transparency, and paste it 30 pixels to the left; then take the original image, give it 75% transparency, and paste it 60 pixels to the left of the original, and so on - So you actually see the original OK, the first copy quite clearly, the second a little less clearly and so on. It makes me think of the "ghosts" you could see with old time TVs when the receiver was a little off-signal.

Maybe the screen doesn't HSYNC correctly on some refresh cycles? If it were a little shifted to the left on 10% of the cycles, more shifted in 5% of the cycles and even more shifted in 2% of the cycles I think you could get something like what I'm seeing.

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Actually, the list in my screenmode editor ENDS at 1024x768x16b, so I can't do that. I had to set manually the 1600x1200x24 mode I'm using (and also try to guess which monitor has the same frequency characteristics as mine, since it is not listed).

Here you can see what I'm talking about (see the morphed icon "repeated" three times to the left).

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If you know your monitors charasteristics, you can just enter them over old values (if you don't, the monitor manual or google might help)

afaik, the selectable screenmodes in the list are selected according to the values you enter.

In another forum (amigaimpact.org), someone suggested that it was maybe related to the cabling, and I think that may be right.

As a matter of fact, a guy had the same problem with a voodoo 4, which disappeared when changing from VGA output to DVI.

The Radeon I own does not have a proper VGA output (only DVI and S-Video, with VGA connected through a cable that connects the card with an external connector which take the place of a PCI card). If the impedance of this "makeshift" connection is not right, all kinds of weird things can happen.

@ winterhunter

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I think you are right there. I have seen this many times myself on various PC's with VGA/CRT. Poor cables and/or low quality gfx cards can give just these symptoms. The most extreme case I saw was when a friend of mine once had an "el cheapo" VGA monitor switch, and the picture quality that came from that was completely unbearable.

Really, you should ask santa for a DVI/TFT solution instead, nothing beats that! After all, this is 2005 (soon 2006)!

@takemehomegrandma:
I will consider getting a TFT with DVI input, but not right away
,unless I really want my wife to kill me; the purchase of a new
computer (the pegII) was quite a tough sale

Besides, I would either need a new KVM, or the place to put the new
monitor.