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Benefits of LCD over CRT

Posted: Sat Feb 02, 2008 3:39 am
by Dirge
I am thinking of replacing my aging CRT monitor with a new and easier on the eyes LCD. What power savings am I likely to see going from a 17" CRT to a 19" LCD? How does this translate into savings on my power bill?

My current monitor is a seven year old Viewsonic E70 and I would likely replace it with a 19" LCD.

Posted: Sat Feb 02, 2008 3:48 am
by Matija
17" CRT power consumption: ~70W
19" LCD power consumption: ~40W

Posted: Sat Feb 02, 2008 6:11 am
by Wibla
An aging CRT monitor has probably not delivered an optimal picture in a while, both because of the aging og components, and lack of re-calibration of colour and brightness during the years, so a new LCD will really provide a lift in percieved image quality.

You should really look for an LCD with a good panel, you should avoid TN-based panels because of bad colours/viewing angles, backlight bleed, lumpy response times (my 8ms LG 24" P-MVA panel feels faster than my 5ms Viewsonic 22" TN panel in games.) Too bad "avoiding TN panels" excludes most 20" and 22" monitors out there...

Posted: Sat Feb 02, 2008 6:30 am
by Matija
Samsung will introduce a 22" S-PVA panel soon, IIRC, and Lenovo has a very weird thing: 22" PVA with 1920x1200. I have no idea who can use such a thing.

Posted: Sat Feb 02, 2008 7:14 am
by Wibla
That sounds good! :)

a 22" with 1920x1200 would be very, very nice for photo editing and stuff that needs high dpi.

Posted: Sat Feb 02, 2008 8:59 am
by Matija
I'm using 1280x960 on a 19" CRT, whose vertical image is roughly the size of a 22" wide LCD (even a bit bigger), and I find it the maximum usable resolution. Even 1050 pixels on a 22" would be too much, I don't even want to think what happens with 1200 pixels :/

Posted: Sat Feb 02, 2008 1:21 pm
by Dirge
Thank you guys those are interesting posts. I will have to look into some of the models a bit more.

Interesting that it almost cuts power consumption in half and I would have far more viewing area.

Posted: Sat Feb 02, 2008 3:54 pm
by scdr
On the viewing area - be sure you get a 19" standard format (not widescreen) if you want to maximize viewing area.
(Widescreens have less area for a given diagonal.)

LCDs don't display darks as well as CRTs. (Getting better, but still may not be as good for photographs as CRTs).

Posted: Sat Feb 23, 2008 7:19 pm
by Shwanzig
LCD's Pros for the Environment

Lead free

use about 1/3 of power consumption

Posted: Sun Feb 24, 2008 12:04 am
by jessekopelman
Matija wrote:I'm using 1280x960 on a 19" CRT, whose vertical image is roughly the size of a 22" wide LCD (even a bit bigger), and I find it the maximum usable resolution. Even 1050 pixels on a 22" would be too much, I don't even want to think what happens with 1200 pixels :/
How could a high a resolution ever be a bad thing? Just change to larger fonts/icons. It can occasionally be a pain to have to play around with text zooms on poorly formated web sites (ESPN.com is the worst), but as monitors with > 100 DPI are becoming more and more common (most wide screen panels and better laptop screens are such) I'm betting things will get better. I've been using a 1680 X 1050 20" monitor at home and at the office for years now . . .

Posted: Sun Feb 24, 2008 12:18 am
by jessekopelman
scdr wrote:On the viewing area - be sure you get a 19" standard format (not widescreen) if you want to maximize viewing area.
(Widescreens have less area for a given diagonal.)
Depends what you are viewing. Yes, most standard format screens actually have more pixels (eg 1280 X 1024 > 1440 X 900) and the extra vertical is very useful for many document layouts, but the extra horizontal of wide screen can be very useful for others. Things better in standard: most web pages, portrait oriented pictures, text documents, some games, and video files of older programs. Things better in wide: spreadsheets, presentation documents, landscape oriented pictures, some games, and video files of newer programs and most movies. Right now, I'd say things are pretty even between the utility of standard vs. wide, with things moving inexorably in the favor of wide. Of course, the best idea is to go with the aspect ratio that works best your own needs.

Posted: Sun Feb 24, 2008 1:44 pm
by ghettojiggalo
i used to have a 24" sun (sony rebadged) crt that literally heated up my 8'x6' room when left on.

i measured the socket power draw of some monitors in my house:

24" crt ~ 125w
24" lcd ~ 40w
46" lcd ~ 97-269w depending on backlight setting.

i'm currently using my 46" lcd at "0" backlight level and it consumes ~97w, less than the old 24" crt i used to have!

Posted: Sun Feb 24, 2008 2:43 pm
by scdr
jessekopelman wrote:
scdr wrote:On the viewing area - be sure you get a 19" standard format (not widescreen) if you want to maximize viewing area.
(Widescreens have less area for a given diagonal.)
Depends what you are viewing.
The observation was purely about area (i.e. square inches), and widescreens do have less area for a given diagonal, regardless of how they are used. (Basic geometry - the squarer it is, the larger the area for a given diagonal.) So at same dots per inch and same diagonal measure, a widescreen can not display as much information as a standard format screen. However, as you observe, some applications are better suited to screens with tall/thin, or short/wide.
So area isn't everything, but one needs to be aware of the difference to avoid disappointment when you can't fit as much of a web page or a word processing document or standard definition television, etc. on the screen as you used to be able to.

Posted: Sun Feb 24, 2008 2:52 pm
by scdr
Since this is the green computing forum, worth mentioning that savings on power bill alone does not make replacing CRT with LCD a green move.
Have to also consider the resources and energy tied up in the CRT (already made) versus those for making a new LCD and recycling the CRT.

As long as it does the job adequately, continuing to use the CRT is probably a "greener" solution (reduces new manufacturing, reuses current parts) and when the CRT eventually does need to be replaced, even more efficient/environmentally friendly LCDs may be available (e.g. might be able to get one with LED backlight, which uses even less power, doesn't contain mercury (less toxic to make and recycle), and may last longer).

Posted: Sun Feb 24, 2008 10:43 pm
by jessekopelman
scdr wrote:Have to also consider the resources and energy tied up in the CRT (already made) versus those for making a new LCD and recycling the CRT.
I've never understood this argument. It's not like the LCD is built to your order -- you are buying something that has already been made. Your buying it consumes no more resources than letting it sit in a warehouse (other than the fuel spent in delivery, I suppose). Meanwhile, your old CRT will die someday and there is no guaranty that there will be a more efficient way of disposing of it a few years down the road than there is now.

Posted: Mon Feb 25, 2008 1:03 am
by scdr
I've never understood this argument. It's not like the LCD is built to your order -- you are buying something that has already been made. Your buying it consumes no more resources than letting it sit in a warehouse (other than the fuel spent in delivery, I suppose).
If the concept of the individual unit that you bought being built before you bought it doesn't make sense. Consider the unit that gets built and put in the warehouse to replace the one you bought. If you don't buy a unit, then that replacement unit never gets built. It works out to the same thing. (Or, consider in aggregate - if nobody buys them, they aren't going to keep making them. It's not like you can't make punch cards (or 5.25" floppy disks, CRTs, 8-track tapes, whatever) anymore, but if nobody buys them, who would bother to make 'em. That is the limiting case, but that limiting case is made up of a whole bunch of individuals not buying.)

Or maybe you believe in some sort of a cargo cult? LCDs just materialize in warehouses, and if we didn't buy them, the warehouses would fill up.
In that case I suppose we would be doing the stores a favor by going in and stealing LCDs to get them some more warehouse space. (After all, don't want them to have to deal with storing all that nasty money that keeps building up either. ;-) Well, Sorry Virginia, there is no Santaclause.
Meanwhile, your old CRT will die someday and there is no guaranty that there will be a more efficient way of disposing of it a few years down the road than there is now.
I don't know much about future disposal tech. What I was mentioning in savings was that the LCD you buy a few years from now is quite likely to be better and more efficient than the one you get today.
LCD tech has been evolving rapidly over the last few years - generally getting better (faster response, better brightness range, larger sizes available).
In addition, we are just starting to see LCDs with LED backlights - which are more energy efficient, no mercury, LEDs generally last longer than florescent tubes (although that may depend on cooling efficiency/etc.)
Since this tech is becoming available now, it doesn't take much of a crystal ball to suggest that it will probably become cheaper/better/more available over the next few years.

As to disposal - a few years ago the matter of disposing of CRTs wasn't much talked about. (Could dump them in the trash even.) Now, many places they are being collected for recycling. So there has been some progress in that area. I am not up on that end of things to know what advances might be in the wings.

Even if more efficient tech isn't on the horizon, by waiting to buy the item you have still slowed the rate of energy and resource use. (Eventually the Sun's hydrogen fuel will be depleted, it will swell up and the Earth will be toast. But just because that will happen sometime doesn't mean it is desirable to have it happen right away. Sometimes delayed fulfillment is a good thing.)

Posted: Mon Feb 25, 2008 12:56 pm
by jessekopelman
scdr wrote:
I've never understood this argument. It's not like the LCD is built to your order -- you are buying something that has already been made. Your buying it consumes no more resources than letting it sit in a warehouse (other than the fuel spent in delivery, I suppose).
If the concept of the individual unit that you bought being built before you bought it doesn't make sense. Consider the unit that gets built and put in the warehouse to replace the one you bought.
I follow this logic, but what happens to the already built units if they never get bought? It costs money to keep things in a warehouse (opportunity cost, as you could be using that space for things that sell), so they will either get thrown away or sold at a loss. Then the warehouse will be restocked with some other model. Will this new model be more environmentally friendly? Maybe. More likely it will just be much cheaper. Manufacturers have huge sunk costs to recover. Rather than reduce production or retool to make a better quality product, their best financial recourse is often to just drop prices on exiting lines (see AMD's response to superior Intel and Nvidia products). Also, this is not analogous to 8-tracks or punch cards. The masses have already decided to endorse this current generation of LCD technology. So, what have you accomplished? The stuff that is already built doesn't magically disappear with no environmental impact and the pace of new stuff being built is unlikely to slow.

Posted: Tue Mar 04, 2008 9:08 pm
by pangit
jessekopelman wrote:The stuff that is already built doesn't magically disappear with no environmental impact and the pace of new stuff being built is unlikely to slow.
It's all down to basic rules of supply and demand. Clearly the manufacturer cannot know in advance if you are going to buy a particular product, but once you've bought it they will know about it.

So if you go into a shop and buy a monitor off the shelf, the data gets logged by the shop and another unit gets ordered from the distributor, then the data is fed back to the importer etc, and finally to the manufacturer. Obviously not one at a time, but every unit sold gets taken into account right up the chain.

This data is then used by the manufacturer to decide on the next production run, so for a popular product that is selling well, they will increase capacity to meet the anticipated demand. Ergo the unit you buy has a direct impact on the environment, just as if it was built to order.

It's the same with air flights (or any journeys on public transportation). You could argue that the plane was going to fly anyway, so my journey has no environmental impact. But that's a completely false argument as the data from your flight (and everyone elses) is used to determine how many flights per week the airline decides to make the next week/month.

Posted: Mon Mar 10, 2008 5:56 am
by kamaleon
Hi, just to throw my 2cents in :)

I currently have a 19" samsung syncmaster 193P, and I can tell you that it only uses 27W maximum. Pretty amazing for a display I should say.

The Lenovo L220x is a dream display for me, but it's out of stock till later on March or April. It's one of the only displays of the size to have a WUXGA resolution 8) AND a PVA panel. The best of both worlds.

The Dell 2407WFP has been reported to use up 57W give or take, I reckon that's pretty amazing for such a big display.

Posted: Mon Mar 10, 2008 11:35 am
by drees
My Samsung SyncMaster 2220WM uses about the same amount of electricity as the 19" monitor it replaced, but only once you turned the brightness down to a sane level.

The default brightness setting is way too bright, the difference between the setting I have it on now and the default was like 25w!

See if you can turn down the brightness on your LCD, you can save some electricity while improving the viewing experience, IMO.

Posted: Mon Mar 10, 2008 11:44 am
by kamaleon
drees wrote:My Samsung SyncMaster 2220WM uses about the same amount of electricity as the 19" monitor it replaced,
Was it a 19" CRT it replaced? how much exactly is that?
See if you can turn down the brightness on your LCD, you can save some electricity while improving the viewing experience, IMO.
Who, me? 27W for a 19" is already VERY decent, I doubt you can find other like-displays with a better consumption :)

Posted: Mon Mar 10, 2008 11:52 am
by drees
kamaleon wrote:
drees wrote:My Samsung SyncMaster 2220WM uses about the same amount of electricity as the 19" monitor it replaced,
Was it a 19" CRT it replaced? how much exactly is that?
It was a FujiPLUS or something like that. It used appx 30w or so, the 22" Samsung uses about the same with the brightness turned down to similar levels.
See if you can turn down the brightness on your LCD, you can save some electricity while improving the viewing experience, IMO.
Who, me? 27W for a 19" is already VERY decent, I doubt you can find other like-displays with a better consumption :)[/quote]
Just try turning down the brightness, you will see. You may find that your default brightness settings are too bright and are actually washed out, anyway!

Posted: Wed Mar 12, 2008 3:46 am
by jessekopelman
pangit wrote: This data is then used by the manufacturer to decide on the next production run, so for a popular product that is selling well, they will increase capacity to meet the anticipated demand. Ergo the unit you buy has a direct impact on the environment, just as if it was built to order.

It's the same with air flights (or any journeys on public transportation). You could argue that the plane was going to fly anyway, so my journey has no environmental impact. But that's a completely false argument as the data from your flight (and everyone elses) is used to determine how many flights per week the airline decides to make the next week/month.
This argument doesn't work. It doesn't take into account the cost of retooling for a change of production. If a model is selling poorly, sales can often be picked up by reducing price. If they are still not selling, models can be further price reduced and dumped on extreme discount channels. Actually changing things at the factory to produce something you think will sell better is often nowhere near as cost effective. This is why production is a lot less sensitive to buying trends than you might think. Meanwhile, running an airline is nothing like manufacturing. No costs are involved in reducing the number of flights to ensure all are close to capacity. Sunk costs can even be recovered by selling the now unnecessary planes to other operators in markets that are still growing (China, India, South America, Africa, etc). You can't conflate the economics of service industries with manufacturing . . .

Good site with tech specs for LCDs

Posted: Wed Mar 12, 2008 6:39 am
by proc
This site is the best source of technical specs for almost all LCD monitors on the market.

http://www.prad.de/en/index.html

Thanks to their review I bought two HP LP monitors: a 1965 and a 2065.
As already stated try to avoid TN panels and you will get better dark tones too.

Posted: Mon Apr 28, 2008 1:11 am
by Tsorovan
Matija wrote:Samsung will introduce a 22" S-PVA panel soon, IIRC, and Lenovo has a very weird thing: 22" PVA with 1920x1200. I have no idea who can use such a thing.
I can. I have one. To be honest the pixel pitch is okay, but it's higher than the dot pitch on the 19" CRT I was replacing (iiyama Vision Master Pro 451) that I ran at 1600x1200@85 Hz. Thankfully it has the same vertical resolution so it didn't feel much of a step down.

The Lenovo can consume upwards to 100 W though (at 100% brightness, but I use it at 0% because LCDs are just too bright), so it is rather hungry. But hey, it's common for 24"+ monitors to draw more power than any old CRT. Plus, the last CRT monitors that were made only drew about 65-75 W and many LCDs approach or go beyond that.

So LCDs aren't as particularly awesome in that department as people like to believe.

Posted: Mon Apr 28, 2008 7:18 am
by kamaleon
Tsorovan wrote:The Lenovo can consume upwards to 100 W though (at 100% brightness, but I use it at 0% because LCDs are just too bright), so it is rather hungry. But hey, it's common for 24"+ monitors to draw more power than any old CRT. Plus, the last CRT monitors that were made only drew about 65-75 W and many LCDs approach or go beyond that.

So LCDs aren't as particularly awesome in that department as people like to believe.
Thanks for that info Tsorovan. When the L220x first came out I was dribbling all over the place wanting one. In the meanwhile I've got a terrific deal on a dell 2407WFP which means an extra 2" (24" vs 22") and I'm not looking back at the Lenovo. I'm really happy with this display, it too has all the things I was looking for on the Lenovo (pva or ips, dvi, WUXGA). I too could have lived with the 22" WUXGA pitch, that's not a problem for me.

On the other hand I don't agree with you when you claim that some crts use less power than lcds. You don't seem to be making an apples to apples comparison - for a start, there are no such thing as 24" crts (not commonly at least) and it's impossible such a beast would use as little as 100W. Secondly, when you claim that 24" lcds use up to 100W, that's at maximum brightness - that sounds a bit unfair. I certainly don't use my 2407WFP at 100% brightness!!! Actually, my wattmeter reads 56W on my day to day usage and I still think i could lower the brightness a fair bit. I think this is pretty good for so much real estate.

Have you checked the power usage of the lenovo at 50% brigthness? That would be an interesting to know.

So as far as I'm concerned, LCDs are absolutely amazing on that department, and it's not a matter of wanting to believe it - my wattmeter is there to be read 8)

led backlit lcds, as well as oleds and oseds will hopefully be able to consume less power in the future, but for the time being, lcd's are a major step forward from crts ;)

Posted: Mon Apr 28, 2008 12:17 pm
by Tsorovan
There are a number of areas you can't always directly compare LCDs to CRTs. Sure, there are LCDs with much larger diagonals, but for the vast amount of LCDs in the market, the resolutions (and pixel pitches) are still stuck in the early 90s compared to the old high-end CRTs. Especially when we come to the stone age pixel pitch of 26"-28" LCDs. So... what to really compare?

Oh and you'd be surprised at how bright most people run their LCDs, I think.

I can't test power consumption at 50% brightness here I'm afraid.

Posted: Mon Apr 28, 2008 12:25 pm
by kamaleon
Tsorovan wrote:There are a number of areas you can't always directly compare LCDs to CRTs. Sure, there are LCDs with much larger diagonals, but for the vast amount of LCDs in the market, the resolutions (and pixel pitches) are still stuck in the early 90s compared to the old high-end CRTs.
there you go again - comparing old high-end models of one technology with vast amount on the market models of another... i really don't see the point. Of course crts have good features. they have their advantages and their disadvantages. Nobody's claiming otherwise :)
Especially when we come to the stone age pixel pitch of 26"-28" LCDs. So... what to really compare?
the pitch of smaller lcds like 22" WUXGA and 24 WUXGA is pretty acceptable... what's the problem with that?
Oh and you'd be surprised at how bright most people run their LCDs, I think.
I actually know that, but then again, that isn't lcd's fault, it's the user's fault. :lol:
I can't test power consumption at 50% brightness here I'm afraid.
oh, i see. Care to explain why? I'm just curious :)

Posted: Mon Apr 28, 2008 12:29 pm
by Matija
I still maintain my opinion that LCDs are a failed technology that's being overmarketed. The only panels really worth using are S-IPS, and those are way too expensive.

Another issue is the - you guessed it - overmarketing of wide gamut. It won't take long until you'll be unable to buy a monitor with accurate colour display.

2010. or 2011. will (probably) finally give us good monitors, be it OLED or S/FED.

Posted: Mon Apr 28, 2008 1:18 pm
by Fayd
a failed technology?

they're a cheap way to display "good" quality images. they do so while saving space and energy costs.

i hardly call that failed.