VOGONS


First post, by GigAHerZ

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Hi,

I have an interesting situation with one ISA videocard, that happens in graphics mode. (not in text mode) It's easiest to just show a picture about it...

Is it possibly one of the few caps that just can't hold a charge any more and that creates this effect?

"640K ought to be enough for anybody." - And i intend to get every last bit out of it even after loading every damn driver!
A little about software engineering: https://byteaether.github.io/

Reply 1 of 8, by brostenen

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If you are using a flatscreen monitor (CRT/TFT), then that is most likely the issue. Only way to get past that, is a different flatscreen monitor, a different vga card or get a CRT monitor. I get these spaghetti lines as well, on anything like Trident, Cirrus logic, ET4000 and more. On all of my LCD monitors. On a few select cards, I have not seen any of these lines. I have an old Cirrus Logic ISA card (can not remember the brand or model) that do not display those lines, and then I have this card below that display the most awesome signal that I have ever seen on an ISA card. None spaghetti lines in Lotus-III or Civilization. Yet using an Samsung monitor, it makes an image with interferance in Dynablaster, yet with an IBM thinkvision, the image is beautifull, bright and without any distortion or loss of colour. Black levels are perfect as well. Only the low compatibility of the ET4000 chip it self is a tiny drawback on this card. Yet I have only seen GFX glitches in Indy500.

Anyway.... The card. If you can find one, then it is a keeper.

The attachment ET4000-ProDesignerII.jpg is no longer available

Don't eat stuff off a 15 year old never cleaned cpu cooler.
Those cakes make you sick....

My blog: http://to9xct.blogspot.dk
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Reply 2 of 8, by GigAHerZ

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brostenen, thanks for the information!

I have this problem with Trident TVGA9000B (on picture) and TVGA8900 (the gradient is not so pronounced). I also have another TVGA9000B that doesn't have that problem and have Cirrus Logic GD5422 that's also fine.

This is why i started to think that maybe it's capacitors or something?

Whenever i will see a possibility to aquire some Tseng cards, i'll definitely do that. Unfortunately haven't had that chance yet.

"640K ought to be enough for anybody." - And i intend to get every last bit out of it even after loading every damn driver!
A little about software engineering: https://byteaether.github.io/

Reply 3 of 8, by brostenen

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New LCD monitors have a problem with synching to the vga signal or something. I can't remember what the exact answer is, so you need to search Vogons for signal on LCD/TFT and old ISA cards. I know it has been explained a few times before. Shure caps can go bad, but in most cases it is the monitor that are struggeling with synching correctly to the card. A bit like the monitor thinks the 70hz signal is a 72hz one, and then tries to compensate, and thereby producing lines of nothingness on the screen. Or it was a different signal value or the other way around. Anyway... The short answer is that flatscreen monitors are the most likely culprit here.

EDIT:
I have seen this on Cirrus Logic VLB cards as well. Actually all VLB cards based on Cirrus Logic. I have seen it on one S3 VLB card, all Trident VLB cards that I have tried. Yet the two Spea Mirage S3-805-VLB cards that I currently own, the lines are so faint that I need to look hard for them. On all PCI cards that I have tried in pure MS Dos (Dos 6.22), I have only seen the lines on a CL-5440-PCI. Even my ET4000w32-PCI does not produce any lines at all.

Don't eat stuff off a 15 year old never cleaned cpu cooler.
Those cakes make you sick....

My blog: http://to9xct.blogspot.dk
My YouTube: https://www.youtube.com/user/brostenen

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Reply 4 of 8, by Baoran

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brostenen wrote:

New LCD monitors have a problem with synching to the vga signal or something. I can't remember what the exact answer is, so you need to search Vogons for signal on LCD/TFT and old ISA cards. I know it has been explained a few times before. Shure caps can go bad, but in most cases it is the monitor that are struggeling with synching correctly to the card. A bit like the monitor thinks the 70hz signal is a 72hz one, and then tries to compensate, and thereby producing lines of nothingness on the screen. Or it was a different signal value or the other way around. Anyway... The short answer is that flatscreen monitors are the most likely culprit here.

I have had the opposite experience. My oldest LCD that is Samsung 1024x768 LCD monitor has the lines with some of my isa video cards, but my newer viewsonic and asus LCDs show everything perfectly.

Reply 5 of 8, by SirNickity

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I use an Open Source Scan Converter to convert my old VGA boxen to HDMI, and then to an LCD TV. So far:

Dell 386SX25 with onboard WDC graphics: No lines.
Orchid Fahrenheit 1280: No lines.
Nameless Tseng ET4000w32i VLB: Lines just like your screenshot.
Matrox Mystiqe: No lines.
Voodoo 5 AGP: No lines.

I have some other newer cards that I've used for testing... some generic PCI and AGP ATI and nVidia boards... no issue with those either. So far it's only the Tseng that does this in my setup. I've been meaning to drop the oscilloscope on it and see what's actually going on.

The one problem I DO have is that the OSSC doesn't have any kind of auto-adjust to H/V sync. And every card, at every resolution, seems to have different offsets that cut off part of the screen. Other than that, it does a really nice job of digitizing all kinds of RGB sources. (PC and various consoles.)

Reply 6 of 8, by CrossBow777

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SirNickity wrote:
I use an Open Source Scan Converter to convert my old VGA boxen to HDMI, and then to an LCD TV. So far: […]
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I use an Open Source Scan Converter to convert my old VGA boxen to HDMI, and then to an LCD TV. So far:

Dell 386SX25 with onboard WDC graphics: No lines.
Orchid Fahrenheit 1280: No lines.
Nameless Tseng ET4000w32i VLB: Lines just like your screenshot.
Matrox Mystiqe: No lines.
Voodoo 5 AGP: No lines.

I have some other newer cards that I've used for testing... some generic PCI and AGP ATI and nVidia boards... no issue with those either. So far it's only the Tseng that does this in my setup. I've been meaning to drop the oscilloscope on it and see what's actually going on.

The one problem I DO have is that the OSSC doesn't have any kind of auto-adjust to H/V sync. And every card, at every resolution, seems to have different offsets that cut off part of the screen. Other than that, it does a really nice job of digitizing all kinds of RGB sources. (PC and various consoles.)

What output mode are you using on your OSSC? I'm asking because I was getting the exact same issue with some graphics getting cut off on the bottom and top. Turns out it only does it on my Sony flatpanel when I use 4x mode. Switch to 5x and it doesn't cut off anymore.

g883j7-2.png
Midi Modules: MT-32 (OLD), MT-200, MT-300, MT-90S, MT-90U, SD-20

Reply 7 of 8, by jesolo

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Have the same issue with my ET4000AX ISA card & S3 805 VLB card. No issues with my Cirrus Logic CL-GD5426/8 cards. PCI cards also don't have this problem.
This is with my old Samsung 2233SW 21.5" LCD.

Reply 8 of 8, by brostenen

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To all.... Yup. Seems like the only solution, is to use old CRT monitor's. Or to use anything from and including 486 with PCI motherboards, combined with something like S3-Trio64v+PCI, S3-Virge325-PCI or CirrusLogic CL5446-PCI. Or simply bite the apple and eighter getting used to the lines or use a bucketload of money on a quest to find the perfect flatscreen monitor.

As an example, then a LuckyStar ls486e motherboard can well be used with Dx2-66 CPU's, and then you get access to those nice cards for near perfect Dos compatibility and no spaghetti lines on the monitor. Personally I run CL-5446-PCI exclusively on PCI systems that are below Pentium-166. Yes it is a personal choice, because I like the image quality it gives and on a system like an dx4, then I see no noticeable speed difference between my S3trio/virge and my CL-5446 cards on such a low spec' system. I do notice the S3's being better on something like a Pentium-133 or Pentium-166. Just not on 486dx4-120/5x86-133 and down.

Don't eat stuff off a 15 year old never cleaned cpu cooler.
Those cakes make you sick....

My blog: http://to9xct.blogspot.dk
My YouTube: https://www.youtube.com/user/brostenen

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