Look for broken/damaged caps around the chip and the d-sub connector.

I bet image is perfect on CRT because those used analog circuity for syncing. LCD monitors scaler will analyze one line of video to determine horizontal timing and will stick to it no matter what. Video adapter might fluctuate horizontal timings slightly, it would be invisible on CRT.

And another one with same symptoms Horizontal distortion/shimmering on Voodoo Banshee
what model of lcd? can you check with another one?

I can imagine it's monitor ~ it's why I only buy/keep LCD displays with a CRT mode =)

Same here with a Voodoo 1. When I use a CRT the distortion is all gone.

Pixel clock phase problem. Could be an issue with the RAMDAC/Clock generator for the VGA chipset. See if your LCD monitor has a phase adjustment.

please list your lcd model number. This for all intends and purposes looks like LCD is somehow interlacing non interlaces source?

rasz_pl wrote on 2024-02-02, 09:10:

please list your lcd model number. This for all intends and purposes looks like LCD is somehow interlacing non interlaces source?

Horizontal banding/artifacting is classic pixel clock phase issues with analog vga input to LCD monitors. Auto adjustment often fails to correctly recover the pixel clock.

http://techmind.org/lcd/phasexplan.html

Hey all, thanks for talking about this. I made a post about the same exact issue last night and your comments here really helped me. Cross-linking for reference:

Re: Horizontal distortion/shimmering on Voodoo Banshee

Thanks again! (Auto-adjust was the ticket to lock in the phase and control per task/application.)