Is VGA that bad on an LCD?

January 11, 2009 7:48 AM

Is it worth upgrading to a 22" or 24" widescreen LCD if I'll be hooking it up with VGA rather than DVI? I know DVI is better, but is VGA that bad?
posted by smackfu to computers & internet (19 comments total)

Yes it is still worth it.

VGA is simply an analog display signal; while DVI is digital. When you start talking about pushing more bandwidth over VGA (more bandwidth because there are more pixels; more color data to send in 60hz) you might start to see a benefit to DVI.

But really -- I have a 22" screen and it does DVI and VGA. When I bought my new video card it was DVI only so I used the DVI->VGA converter. When I finally bought a DVI cable and plugged it in -- I was amazed at how little it actually did.

The difference is minor -- a good VGA cable will probably look nearly as good as DVI in many cases. (A cheap VGA cable -- however).
posted by SirStan at 7:55 AM on January 11

The difference isn't major (and sometimes unnoticeable), but it can depend on the cable and the monitor. My cheap desktop 17-inch display had semi-noticeable moving pattern lines when run on VGA, but DVI cleared that right up. The lines looked something like this, although nowhere near as strong or annoying.

If you've got the chance to check it first, do that. Otherwise, I'd go for a monitor that has both inputs.
posted by sektah at 8:04 AM on January 11

It depends, but I'd say yes, go ahead and do it. I'm using a 24" LCD via VGA (and have been for a couple years), primarily because my nice 4-port KVM doesn't support DVI.

The quality of the image will depend on your setup. The computer I had when I first got the monitor introduced a fair amount of noise into the image, due to electromagnetic interference from other components (I suspect my TV tuner card was a big one). The image always sort of shimmered or pulsed. I think 1920x1200 is a lot to ask of a VGA signal. Trying different refresh rates, I was able to find one that was acceptable, but never perfect.

This is the kind of thing that will vary from computer to computer. When I upgraded to a newer PC, most of the video issues improved significantly. However, I can still see some improvement in crispness when I use a computer connected to the DVI port of my monitor.

The question of whether it's worth it or not? Absolutely worth it. I love the screen real-estate for working in a few apps simultaneously. Movies and games look great on it. VGA isn't so bad as to be unusable, but I do look forward to converting to 100% DVI some day.
posted by knave at 8:06 AM on January 11

I'm using a 24" LCD via VGA (and have been for a couple years), primarily because my nice 4-port KVM doesn't support DVI.

Interesting, that same scenario is what prompted the question. 4-port DVI KVMs cost almost as much as the new monitor would.
posted by smackfu at 8:43 AM on January 11

I'm using a 22" monitor with the VGA cable that came with it, and no problems. Both monitor and card have DVI, but I've had no reason to go buy a DVI cable. It's just a hunch, but I'd suspect a cheap video card to be much more of a problem than using the analog connection.

I really only have two complaints. The native resolution is non-standard and has thus caused me issues on occasion, although I think that was when I was running Linux and using a KVM to switch between it and my Windows box. The other complaint is also the native resolution. While it has wider resolution, things are large, I'd prefer to make more use out of the 22" if the native resolution was larger.
posted by hungrysquirrels at 8:44 AM on January 11

VGA isn't that bad.

Under most circumstances you'll never notice a difference.

I'll give you some purely anecdotal evidence from my experience:

I had two monitors on my computer, now I have three. I originally had a 15 and a 17 inch LCD, hooked up to the on board video (VGA) and a cheap old graphics card (also VGA). Picture quality was fine.

I upgraded the video card and now I have three monitors in this arrangment 15 on DVI, 17 on DVI, and the new 15 on the old onboard VGA.

I've got all three of them at their maximum resolution and I haven't noticed any degradation in quality. The new video card wasn't top of the line either, just your average $60 deal with a good rating at NewEgg.com.

Oh and for what it's worth the two 15 monitors are identical brand/model number and I notice no difference between the quality of them running on two separate video sources and in DVI and VGA respectively.
posted by JFitzpatrick at 8:45 AM on January 11

VGA is fine as a cabling method; image quality will come down to the quality of your hardware. I have a very nice 42" HDTV (1980x1020) being powered by a laptop over VGA, and the signal is crisp and clean with a $10 VGA cable. I have a mediocre 24" monitor, and the VGA signal is noisy whereas the HDMI inputs are very clean, because the monitor was poorly designed.
posted by ellF at 9:37 AM on January 11

VGA is fine until you've used DVI. Then you can't go back.

Extra pixels is always worth it. Once you go 30" you never go back.

Seriously; the 30" monitor has really improved the quality of my life, both at work and at home. Make yours part of your next job offer.
posted by jeffamaphone at 10:10 AM on January 11

I have a 23" that takes both DVI and VGA. I have one computer attached to each and can push a button that switches between them.

There is exactly no difference between them. (I was a graphic designer for a few years and have an eye for this sort of thing.) However my VGA cable is overbuilt, shielded, thick as my thumb and has ferrite beads at both ends. DVI cables (like HDMI cables) can be very cheap and work perfectly.. Analog cables not-so-much. And a kick-ass VGA cable might well increase the cost so much as to be no difference.
posted by Ookseer at 11:28 AM on January 11

You'll love the additional real-estate so much that you probably won't even notice any difference.
posted by furtive at 11:49 AM on January 11

VGA is fine until you've used DVI. Then you can't go back.

Not true - if your monitor has good quality ADCs, then you won't be able to tell the difference between DVI and VGA.

A long VGA cable or KVM may degrade the signal enough to make a difference though.

You'll love the additional real-estate so much that you probably won't even notice any difference.

Also not true - if too much noise gets onto your signal, the screen will become fuzzy and that extra resolution will be unusable.

If you are buying the cheapest model in the range, the VGA quality will probably suck.
posted by b1tr0t at 12:09 PM on January 11

I use a 24" Acer at 1920 x 1200 using a VGA cable with my MacBook. It works fine - not great, and it required a bit of manual tweaking - but it's perfectly acceptable.
posted by adrianhon at 2:12 PM on January 11

VGA can work just fine even at 1920x1200.

The most common VGA problem with LCD panels is ringing, caused by signal reflections inside the VGA cable. Visually, this looks like a very small version of TV ghosting. The fix is to get a better VGA cable. Usually the one that comes with the monitor will be fine, but if you're using a KVM switch you might need to upgrade the cable that goes to the switch.

The next most common VGA problem is shimmery or flickery columns of pixels. This happens when the analog-to-digital hardware inside the monitor isn't perfectly phase-locked to the incoming video signal. There is usually a menu item available via the monitor's front-panel buttons that will fix this: look for a pair of controls labelled something like "clock" and "phase". Get the clock right first, then fix the phase.

The main advantage of DVI is that you just never have to fool around with this stuff; plug DVI in and it just works. But there is no visual difference at all between a properly set up VGA-connected panel and a DVI-connected one.
posted by flabdablet at 3:12 PM on January 11 [1 favorite]

Assuming the screen is good, the cable is good, and your graphics card is good, VGA is a fine transfer standard for just about any resolution.

I've got my computer hooked up to our HD LCD TV as its monitor. I started out on VGA, and then switched to DVI (on HDMI). I was disappointed that I couldn't actually see any difference in sharpness; the color saturation did ever so slightly slightly improve when I switched, but I blame nVidia's weak RAMDACs more than VGA.
posted by Netzapper at 3:15 PM on January 11

I have a 20" monitor that can use both DVI and VGA, and I used DVI as my standard connection. I have used the VGA connector when repairing a second machine, and the quality is only slightly lower with a decent cable. I've used low quality cables and then there are serious problems with ghosting and general "fuzziness." Just make sure you get a good quality cable (set of cables actually since you're using a KVM. Make sure they have ferrites, as those cut down on the noise that can be picked up, and I would recommend keeping them as short as possible to reduce the chance of interference from other electronics.
posted by borkencode at 3:40 PM on January 11

I had a 22" which was running DVI, then a switch to a new laptop prompted use of vga until HDMI-DVI cable could be sourced. Most software - everything worked just fine, but in AutoCAD I had some problems, the lines looked 'fuzzy', even a straight vertical or horizontal. This is an ACER 22" - not super expensive, and I'm sure the VGA cable is just some cheapie, but in this case going back to DVI was a real treat.

in summary - VGA is not bad, DVI just fine tunes those razor-sharp edges. You'll probably be fine for normal text stuff.
posted by defcom1 at 5:12 PM on January 11

Thanks all. I was honestly expecting much more dire answers. I'll give the VGA a try, and if it has problems, I'll first try a better cable, and if that doesn't work, then I'll spend the few hundred to upgrade my systems to DVI. (Or just return the monitor.)

Extra pixels is always worth it. Once you go 30" you never go back.

Doesn't a 30" have other complications, like requiring dual-link DVI and stuff? Also it would cost about 3x what I'm looking to spend and would be bigger than my TV.
posted by smackfu at 6:19 PM on January 11

Doesn't a 30" have other complications, like requiring dual-link DVI and stuff? Also it would cost about 3x what I'm looking to spend and would be bigger than my TV.

I run a 42" HDTV at 1920x1080 at 60Hz (highest the TV does) using a single DVI line. Now, if you're doing super high resolution or refresh you might need another line. But, the size itself has no relation to anything. Hell, you can make a 60" 640x480 television and drive it from NTSC... my rich friend had one when I was 14.
posted by Netzapper at 7:23 PM on January 11

Like Ookseer, I have a 24" (Samsung) that is connected to both a PC (by SVGA cable) and a Mac by DVI. Zero difference in quality.

Also, more pixels is always always worth the extra money.
posted by rokusan at 11:39 PM on January 11