Rippling effect on QP-VGA4 \ VOGONS

Rippling effect on QP-VGA4

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First post, by KostyaJRZ

Posted on 2024-04-23, 16:44

KostyaJRZ Offline

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So I have isa graphics card from 1990 by Chips & Technologies named QP-VGA4 based on F82C450. It gives this crappy rippling effect, mostly visible during booting, but it is present almost always. I'm just wondering is it actually gpu problem or maybe changing some capacitors or etc. would fix it?

Here's video of what's happening: https://youtu.be/qPp8GRqUC2o

Card photo:

The attachment IMG_20240423_192819470~2 (2).jpg is no longer available

Reply 1 of 3, by dominusprog

Posted on 2024-04-23, 18:36

dominusprog Offline

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Well, changing the caps, especially the tantalum ones, is a good start.

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Reply 2 of 3, by rasz_pl

Posted on 2024-04-24, 01:28

rasz_pl Offline

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I suspect LCD monitor, looks like those ripples on Voodoo3 with monitors that fail to properly sync.

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Reply 3 of 3, by Jo22

Posted on 2024-04-25, 09:14

Jo22 Offline

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common mode interference, maybe ?

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