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Does the VGA cable matter?

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First post, by TandySensation

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Will a high quality VGA cable improve the image on an LCD?

All of the D-Sub VGA video cards I've tried have minor display issues on an LCD, some are better than others but all of them to some extent have banding, blurriness, gray instead of black background, or text shimmer. It's an 22inch 1920x1080 Asus LCD, it does support a 4:3 aspect ratio option but that doesn't improve the image.

DVI looks best on it but my old computers have trouble using newer video cards.

Is it worth getting a 'high quality' VGA cable or will I see no difference? I'm using the one that came with the monitor. It's kind of thin, has ferrite beads at each end with blue connectors.

Don't really have room for a CRT or a smaller LCD and wanted to know if anyone has tried different VGA cables and if they noticed a difference between them. Internet searches turned up results from both camps, some say no difference and some say it will improve.

Reply 2 of 25, by Reckless

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Agreed. At work many years ago I was provided a cheapie VGA cable and had very poor quality image on a 19" CRT. I got it swapped for one with proper shielding and the difference was night and day.

Reply 3 of 25, by swaaye

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Post a photo of the cable you are using.

Cable quality has an impact at higher resolution + refresh rate. Higher bandwidth signals, in other words. LCDs usually operate at 60Hz so those thin cables can be adequate all the way up to 1920x1200. Cable length is also a consideration but you are probably using a ~6ft cable I'd guess.

My guess would be your problems are actually caused by the video cards. VGA signal quality varies wildly among video cards.

Reply 4 of 25, by obobskivich

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Agreed - cable quality can matter, but length and the environment also matters. If you're trying to hook up a high bandwidth signal in a fairly noisy environment with a long, cheap cable, that's probably a recipe for disaster. On the other hand, I've not had many issues with "lesser" (not fully unshielded/no-ferrites but not garden-hose-thick) 3-6ft cables at home, especially running lower resolutions.

Something else to keep in mind - older computers usually don't have flawless analog outputs, especially at higher resolutions, so that may be part of the issue here too.

Reply 5 of 25, by TandySensation

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It's about 6 feet long. Video quality varies between the cards I've tried. Modern cards look fairly good. I'm mostly in 640x480 60hz in DOS or 1024x768 60Hz in 98SE. All with the same cable so it must just be the cards themselves. I bet they'd look better on a CRT but I haven't been able to find one that's not junky and not sure I want to collect anymore bulky computer stuff.

The slight blurriness gives me a headache. A 4:3 15 or 17 inch LCD might give a better image, it might scale the image better than my wide screen.

I must be spoiled with DVI and HDMI on new hardware or my eyes from when I was a kid didn't mind the slight blurriness or flicker. This is mostly nostalgia for me and my eyes from 20 years ago were much better nor did I work in IT looking into computer screens all day.

Anyone else here work in an office looking at a computer all day? It wears on you and kills some of the joy of computing during off hours.

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Reply 6 of 25, by swaaye

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Yep I stare at screens all day and I hear ya about it.

A CRT may or may not be better. I started to notice blurry cards back when I had a 17" CRT and started using higher resolutions at more than 60Hz. Low resolution games do look better though I would say. LCD interpolation is not super, and the response time ghosting doesn't help either. But I too don't have a CRT anymore because I don't want its bulk around.

Reply 8 of 25, by TandySensation

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Update: ordered a refurbed 17 inch LCD(LCD1770V-BK) and the highest looking quality VGA cable(Nippon Labs SVGAMM-6) I could find at the egg. I'm hoping it will be easier for a small 4:3 LCD to scale the 640x480 image than my wide screen trying to approximate it.

Picked the super slow shipping, when it arrives I'll do some testing with the cable on my current monitor and with the small one and report back if it's better or not. Below are the cards I plan to test with.

ISA 8900D - Looks Poor
ISA CL5429 - Looks OK
PCI S3Trio64+DX - Not good in DOS, grayish background with lines, ok in Windows
PCI RageII - Looks fairly good in both DOS+Windows(has a lot of parts on the board- looks expensive)
AGP RageIIc - Terrible in both dos and Windows, cheapo card when it was new.
AGP TNT2 - Decent
AGP Rage 128 - Decent
AGP Geforce5700le DVI - Looks awesome - gold standard but unstable on any of my Socket 7 boards.

Reply 9 of 25, by HighTreason

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I can tell you one thing about VGA cables. Go beyond 3 Meters long and it doesn't matter how good the cable is, you will get color bleeding. At this length the cable quality makes a very noticeable difference, so does the horrid ground loop that hangs around my capture gear. I thus imagine that cable quality always makes some amount of difference, but how much will differ depending on video card, monitor and the environment it is operating at. In this room, you cannot receive any radio signals other than the interference generated by devices in the room itself, so my signal cables don't have an easy time of it, any inadequacy in the shielding becomes apparent rather quickly.

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Reply 10 of 25, by 133MHz

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I remember not being able to see the difference between DVI and a high quality VGA cable, but crappy cables went from a slightly soft picture to a full-on ghosting blur-fest, even in SVGA/XGA.

I've seen both good and bad versions of the cable shown in the picture, the only way to tell them apart is to try it or to cut it with a knife and look at the wires inside. 😵

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Reply 11 of 25, by Jepael

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Picture quality is a product of the whole system, the video card (and maybe even noisy parts like PSU or hard drives near it), the cable, and the monitor.

Blurriness is a definite sign of bad something that causes attenuation of high frequencies, usually the cable though, but it could be bad filtering on VGA card or monitor side as well.
Ghosting means the signal is able to reflect back and forth and it does this because there is an impedance mismatch because of bad cable or bad monitor.
Text shimmer just means the monitor samples the video signal just when the VGA card is updating the analog value while the monitor should sample when analog value is stable, so either monitor assumes incorrect pixel clock (this can be fine tuned) or then there is some kind of jitter, perhaps from unstable/noisy HSYNC signal through long cable.
Sometimes, VGA cards don't have any filtering on their output, and some TFT panels have a hard time to achieve good quality picture with them.

Gray instead of black has nothing to do with the cable, it is not able to make colors brighter.
Color banding is also not caused by the cable, it is not able to limit the colors.

So yes, usually a better cable improves the system, but it is very hard to know just by the looks of it if the cable is of good or bad quality. For example, the plastic blobs may contain ferrite beads, or then they are just plastic blobs to make it look like a good quality cable.

Reply 12 of 25, by GeorgeMan

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The problem is:

What can you do if your CRT has an embedded vga cable and it starts to show artifacts on screen due to year passing by?

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Reply 13 of 25, by PhilsComputerLab

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I have one 3m long VGA cable, quite old, but very thick, and it's my best cable. Beats all the new ones, and I have many types, that I recently collected.

Good thing is however, that once you "need" higher resolution, you usually got a digital interface anyway. Up to Voodoo 3 or so, I like to play at 1024 x 768. A good compromise between image quality and performance.

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Reply 14 of 25, by raymangold

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The shielding of the VGA cable and the way the LCD interprets it seems to have some sort of correlation.
For example, one LCD I owned I had to set the refresh rate to 60Hz on cables that were heavily shielded in order for the picture to become clear, or 75 Hz for cables that had hardly any shielding. And the reverse for other LCDs for some reason...

GeorgeMan wrote:

The problem is:

What can you do if your CRT has an embedded vga cable and it starts to show artifacts on screen due to year passing by?

Solder on a discreet VGA connector or replace the cable with one that has better filtering (which will also most likely require soldering due to a presumed proprietary connector on the receiving end internally).

Reply 15 of 25, by RacoonRider

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I've got a really thick 1.8m VGA male-female cable with beads that I use as an extender for my 17" IBM CRT, which in turn has a very thick cable over 1.8 meters long. I do that because I plug and unplug the cable all the time and thick cables tend to be fragile at the base, where they die of wear. The extender protects the monitor cable, which can not be detached/replaced.

Anyway, with almost 4m of quality VGA cable I have a great picture. Even though signal is most probably degraded, it's beyond spot even at 1600x1200.

Reply 16 of 25, by Darkman

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a quality VGA cable will make some difference , though how good your monitor/graphics card, as well as the length of the cable.

For instance the S3 Virge card I used had significantly worse output at higher resolutions (the screen would actually judder at any res above 800x600) while using an IXOS VGA cable which has the thickness of a garden hose.
On the other hand the Matrox Mystique or ATI Rage cards had great output with just a normal cable.

Reply 17 of 25, by TandySensation

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Finally have both a 17inch LCD and a thick quality VGA cable.

Tried a few different video cards and switched between the 17" and the 23" wide screen using both cables. The heavier VGA cable is better than the thin one, especially on the larger screen. It's not DVI quality but it's an improvement when using old cards with a larger LCD that's trying to stretch the image out. It nearly fixed the poor image from a 2MB S3Trio card but it didn't do anything about vertical bands snaking down the screen from a Rage IIc, I believe the IIc to be defective.

The 17inch monitor is better than the 23 all around, the difference between the two VGA cables isn't as noticeably on the smaller monitor. Using the fine tune controls on both monitors also helped. I noticed in Windows 98 when you go to shut down the background turns darker and will flicker until the fine tune is adjusted. This might be a good way to get the adjustment right if you have 9x installed.

Bottom line: The smaller 4:3 monitor is closer to period correct hardware and looks better all around but a good quality cable doesn't hurt and may help. There is a difference between cards, some are better than others but even my worst one looked better with the heavy cable with the large monitor.

Might be easiest to just get a DVI video card and be done with it but it's fun to use the original cards and I've had limited success getting a card with DVI working on my Socket7 VIA boards, they are difficult to make stable.

Reply 18 of 25, by PhilsComputerLab

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This might be of interest: StarTech VGA Splitter - Improving signal quality

The StarTech VGA Splitter is very good and improves the image quality on my setup. Don't know how, but it does.

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Reply 19 of 25, by TELEPACMAN

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philscomputerlab wrote:

(...)
Good thing is however, that once you "need" higher resolution, you usually got a digital interface anyway. Up to Voodoo 3 or so, I like to play at 1024 x 768. A good compromise between image quality and performance.

Same here 😀 My personal experience is, particularly with TFT above 19", you have to have a DVI-to-DVI connection.