75 Ohm Terminators why?

[vol.2]

Originally Posted by Alex KL-1

This impedance matching issue can harm more with basically-VHF signals from eg. 1600*1000 @ 85Hz or more for analog RGB monitors; this requires a lot of bandwidht, making mismatch readily visible. I have a Dell P991 (Sony chassis) operating at 1600x1200 (at 75Hz), and even a little loss of conduction from VGA connector makes ghosting.

I have a similar era Dell/Sony at 1600x1200. It works well, but it does smear and ghost at lower white levels than do most of my other PC monitors. It's certainly less prone to doing so at lower resolutions. It's got optional BNC connectors on the back, so I have considered looking for a cable I can use for that input to see if it works any better. Unfortunately, I only have a DVI-I output on my video card for an analog signal, so I would have to find a BNC to DVI cable. Really not sure if it's worth spending the money on it and if it would make any difference in the headroom at all.

Maybe it's an impedence issue and the cable itself won't help?

[ppppenguin]

Poor quality cables can cause significant problems with high resolution analogue monitors, even if the terminations are good. At 1600x1200 it's very hard to make analogue interconnection look as sharp and good as DVI or HDMI.

[Alex KL-1]

Originally Posted by vol.2

I have a similar era Dell/Sony at 1600x1200. It works well, but it does smear and ghost at lower white levels than do most of my other PC monitors. It's certainly less prone to doing so at lower resolutions. It's got optional BNC connectors on the back, so I have considered looking for a cable I can use for that input to see if it works any better. Unfortunately, I only have a DVI-I output on my video card for an analog signal, so I would have to find a BNC to DVI cable. Really not sure if it's worth spending the money on it and if it would make any difference in the headroom at all.

Maybe it's an impedence issue and the cable itself won't help?

Mine uses the CDP4402 chassis. Probably, it's video bandwidth is not perfect for high refresh rates + resolution (plus the reason that ppppenguing mentioned), so, since I use it more for "retro" gaming, I use only 1280*1024 @ 75Hz for workspace (is plenty for it's actual usage), 1600*1200 for modern games, and lower for old games.

[vol.2]

Originally Posted by ppppenguin

Poor quality cables can cause significant problems with high resolution analogue monitors, even if the terminations are good. At 1600x1200 it's very hard to make analogue interconnection look as sharp and good as DVI or HDMI.

I've got a good cable on there now. It's a DVI-A to VGA cable, and it's very thick and has ferrite beads on it at the ends. I can't remember the maker as it was purchased decades ago, but it was a good expensive cable.

I'm mostly concerned with whether or not the BNC inputs will give me better quality and less reflections at higher resolutions than the VGA cable does, given a similar quality of cable.

At the time (like late 90s/ early 2000s), I remember people telling me that it's not worth it and I'd never tell the difference, but Sony seems to claim the BNCs are better when using the monitor at it's limits.

[ppppenguin]

I doubt it will make much difference if you use the BNCs but you never know. Analogue video bandwidth of around 60MHz over co-ax was never easy. Everything has to be right, from the graphics card (not always as good it should be) though the cables and monitor itself.