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Do Later LCDs Need Screen Savers?
bwdunn asks: "Do we need to run screen savers again to prevent the burn-in we saw on the very old CRTs? Dell's latest and greatest laptops, the Latitude D800 and Inspiron 8500 both suffer from horrible screen burn-in problems with burn-in visible after as little as 2 hours. Dell claims this is an industry wide problem. The high end displays from Apple also seem to have this problem. I have never seen this problem before 2002. Is this something new due to inferior LCD screen manufacturing compared to screens from just a few years ago?"
The toasters are going to fly again, gentlemen...
Otherwise someone might not see your laptop on the floor, and step on it...
Sounds crazy to me. Got three LCD panels at work that basically sit around displaying the same thing for 12 hrs a day (when we are not there).. I wasn't aware that it was -possible- for an LCD to burn...
"Champagne for my real friends - and real pain for my sham friends!" http://ericblade.postalboard.com/
The local department has recently been replacing the CRT displays in the computing labs with LCDs as part of their rolling upgrade cycle. So that it's easier to distinguish between a working PC and a dead one by whether or not the login screen is showing, we turned off the screensaver -- thinking that ``there's no phosphor to get burned in.''.
Doesn't appear to be true, sadly. A number of displays are now starting to get a burnt-in image of the login window.
Time to update the login manager scripts with a small call to xscreensaver, methinks..
The answer (at least for Dell) is in the forums that were linked to in the summary. Send it back. Get a new one. If the new one also burns in, do it again. Do it until you get an LCD that doesn't burn in. It's a major hassle, but it appears that all of their LCDs don't suffer from this problem, thus it's unlikely that "new" LCDs have this problem. Looks like a bad batch or poor construction somewhere in the laptop/LCD, since replacing the LCD will eventually get rid of the problem.
I don't know about you guys, but I was never a fan of wasting power. All my PCs turn off the monitor when idle!
Do you drive an SUV too?
Here. Picture after 15 hours of burn-in and 51 hours of uninterupted reconditioning.
Lars T.
To the guy who modded me down from perfect to terrible Karma - Apple haters still suck
Iâ(TM)ve had five Dell C810 Latitude laptop screens (over three machines) that all exhibited this ghosting problem. Kits from work, so they were under warranty. No problems with any of the thinkpads or the Dell Precision M50 (?), so Iâ(TM)m willing to bet Dell cut some corners on the Latitude series.
Industry problem my assâ¦
+++ UGUCAUCGUAUUUCU
But AfterDark works only in Win9X!
I wonder if anyone's ever going to make a freeware version of it, or a linux version.. I bought AfterDark because I liked it so much, and then I moved to W2K and AD was gone. I'm stuck with the "Starfield simulation" since then.
hemi
I bought a Dell Inspiron 5000E about three years ago (they are no longer made) with the expensive 1600x1200 LCD display.
Luckily, it doesnt have this problem. Ive used it every day for three years and not had any burn-in. None. Zero. Zip.
Another reason I'm glad my LCD doesn't have this problem is this: the energy saver just turns off the backlight. I can shine a bright flashlight on the display and see that the liquid crystals are actually still displaying the screen. Once I even moved the mouse pointer around while the backlight was off, and I could see it with the flashlight. (There is a button which turns off the backlight. It is positioned so that shutting the lid pushes it.)
Some screen savers also have a tendency to use the same areas of the screen, so watch out. "Blank Screen" is probably best because it really does set all the pixels to black, whether the backlight is on or not.
I wonder whether it is black or white which causes the pixels to "fade."
Sunlit World Scheme. Weird and different.
My mother, for instance, wastes more power than she saves by going around turning off all her fluorescent lights. Aren't LCD monitors designed in the same way? They only use power when they are updated?
"I assumed blithely that there were no elves out there in the darkness"
The backlight in LCDs uses the most power
I've noticed that LCD screens of powerbooks slowly "fade" away. is this some sort of feature designed to prevent burn-in or just another feature designed to save battery power?
...TROGDOR THE BURNINATOR!!!!
Well, I was going to post a reply to the effect of "aren't those fluorescent, so they waste energy turning them off and on," but it turns out I was wrong about that and this site has a very good explanation of why that used to be true but isn't any more.
"I assumed blithely that there were no elves out there in the darkness"
I have two flat-panels on my desk at work, one of which is a Dell that I've had for about a year. I've never had a problem with burn-in on them, but:
(1) I've set up my screensaver to power off the screen after 5 minutes of inactivity.
(2) I press the power button to turn the screen completely *OFF* when stepping away from my desk - even if it's only for an hour at lunch.
These strange manual power-saving methods of pressing a switch.. it's strange, I tells ya.
If the had read the til from apple, they would not have said it is burned in because it really is a temparory problem that can be fixed according to the atricle.
If you want to not burn in a lcd, turn it to white. This is the state where an lcd is actually off. The black position is fully powered.
From the Apple LCD FAQ :
... is that somehow also burning it in a different direction, possibly also causing damage? I would think not, but I thought that LCDs were immune to the effect in the first place.
3.1 - Q. I have noticed that my screen is showing some burn in when left with the same image for a long period of time. I thought LCDs were immune to 'burn in'. What should I do?
A. In the event of a mild or even strong burn in, unplug your LCD, lift it off the table and orient it with the screen down, parallel to the Earth. Now shake it all around. The silver powder in the unit will spread all around, returning your display to the original condition. When putting the display back on your desk remember that the two knobs go on the bottom.
-:-
Oh wait, that was from my Etch-a-Sketch.
That said, I read what Apple has to say on the matter and now I wonder - why are LCDs 'burning in' in the first place, and by blasting it with a bright white image to restore the screen
Glonoinha the MebiByte Slayer
What with a new $80 shipping and handling charge for warranty repairs.
"Eve of Destruction", it's not just for old hippies anymore...
Sounds crazy to me. Got three LCD panels at work that basically sit around displaying the same thing for 12 hrs a day
You sure they're not just burnt in?
Actually it can be done either way. A liquid crystal, when powered, rotates the polarization of light 90 degrees. When unpowered it has no effect. So, a LCD display is made from two polarizers and a layer of liquid crystals. Consider this:
Whether white or black is powered depends on the way the display is made.
Sunlit World Scheme. Weird and different.
You'll be so busy compiling stuff.... not one thing will be displayed on that screen constantly!
Kills burn-ins too...
---The Gentoo Troll
I have a SAMSUNG 171v
It's a 17" analog flat panel LCD screen. I've had the same desktop "image" displayed for an entire weekend one time (with no DPMS to power it off).
Checked it on Monday and it was like new. not even a slight ghost of a burn in.
This problem must be dependant on certain factors because it isn't universal.
I'd rather be a conservative nutjob than a liberal with no nuts and no job.
-- ;-)
Kuro5hin.org: where the good times never end.
What most people ignore are the facts that once you touch an LCD screen is that it really can't get cleaned right. People sneeze on the screen and touch the screen and on laptops, keys will etch into the screen. What we NEED is a clear, thin plastic screen to go over the LCD to prevent things like dumbass girlfriends getting their fingerprints all over my nice 15 inch laptop screen.
- Zav - Imagine a Beowulf cluster of insensitive clods...
I don't have a problem with burn-in- but I use the screen saver- more important is to shut off your backlight- they have a limited lifetime, and will lose intensity over time.
CUT CORNERS? Are you joking me? The Dell Latitude series has been a joke to me for years. While I haven't used any of their more recent machines (about 2 years), I can safely say that there is absolutely no justification for the Latitude's inflated price.
They are not durable, they don't perform well compared to the competition, are poorly built, and (with a few exceptions) weigh a ton. While Dell's Inspiron line isn't exactly great, they're priced accordingly.
The high-end notebooks from other companies, however, such as the IBM thikpad do indeed show improved quality which reflects their high(er) price. If you've ever used or felt one, you can see that they are very sturdily built.
When all else fails, you could always get an iBook. Cheap,
and well-built to boot.
-- If you try to fail and succeed, which have you done? - Uli's moose
and make sure to pick a design you can live with for the duration ... on this note, why not use your name? That laptop will always be traceable no matter how far it walks or runs ....
Laptop Rule One: Laptops have legs and will run away as soon as you turn your back on one. especially once you've given it a lot of data.
Words to men, as air to birds.
That's because you're whipped, man. Grow a set of balls.
I have had my Apple 15inch LCD which I bought with my G4 for the last 2 years, and it has only been turned off TWICE since I bought It, and both times were only while I moved it. In all that time at maximum brightness, without a screensaver running, I have never once had any issue of screen burn.
_______
Death wish, n.:
The only wish that always comes true, whether or not one wishes it t
If that's the case, then dark screensavers would not actually help as I previously thought.
Many household devices today use more power when their state is changed than they would if they were just left on constantly.
Go get yourself a meter like the WattsUp and gather some stats. In my experience, for computers there is an initial power surge that is maybe 2-3x normal draw, and lasts anywhere from 20 seconds to a couple of minutes. So worst case, if you will be turning your computer on again within 6 minutes, you probably should leave it on. Otherwise, turning it off will save power.
For screens, it's more complicated; CRTs draw more while warming up, but only for 15 seconds or so. But they draw less when showing a fully black screen, and different resolutions draw different amounts. Also, modern CRTs have assorted sleep modes. So whether or not to turn off a CRT depends on your usage patterns. For LCDs, I have no data.
I was also interested to note that high CPU usage produces measurable extra power usage. On a dual-processor P3/733 system, each processor pulls an extra 10 watts under load. So it turns out that things like SetiAtHome aren't free.
My mother, for instance, wastes more power than she saves by going around turning off all her fluorescent lights.
A common misconception, but not true. See this article for the details. They recommend leaving them on if you'll need them again within 15 minutes. But this isn't because of power usage; it's because turning them off and on too often reduces bulb life.
Aren't LCD monitors designed in the same way? They only use power when they are updated?
You'll note that in a dark room, you can see the LCD just fine. This means that it's producing light, which takes power. According to this week's Economist, "an LCD is only 10-15% efficient at converting energy from its power source into a readable image."
I was also interested to note that high CPU usage produces measurable extra power usage. On a dual-processor P3/733 system, each processor pulls an extra 10 watts under load. So it turns out that things like SetiAtHome aren't free.
This is because rathering then executing self: jmp $self in the idle loop, the operating system typically uses the HLT instruction which puts the CPU into a low power (unclocked) state until an interrupt is received (typically the timer interrupt, meaning the scheduler needs to run again).
You will note that no matter what kind of program you run, it'll draw the same amount of power as long as the load % is the same. The exception might be an app that steps all over the cache, triggering memory to work hard.
THIS THING CAN TURN ON A DIME, MACROSSZERO STYLE ALSO FUCK BETA, ~NYORON
The Dell Latitudes are not marketed to people who want high performance machines. They're marketed to people who want to be certain that if they order multiple machines with identical specifications they'll get multiple identical machines. Not only will you get several identical machines if you order them all at once (which is much more unusual than you may realize), but you'll also be able get identical machines if you order them again three months later (which is a much more common requirement than you may realize). And, you'll still have identical machines after the various warranty replacements you'll inevitably have over the next three years.
If you don't get any value from having multiple identical machines, then you don't want to buy Dell Latitudes. They don't offer anything of value to you. But don't act as if that means they don't offer anything of value to anyone.
Slashdot is jumping the shark. I'm just driving the boat.
Timex TMX watches have (I swear!) a "screen saver" function. It also has a handy magic-8 ball function. See here for an example. Endorsed by Lara Croft too!
Actually, the "value" in Dell Latitudes is that they are totally generic Taiwan bricks with some Dell plastic on it, thus making them very cheap.
IBM sells various small/light/fast/durable models and still can get you identical machines with interchangeable parts.
The problem could be that manufacturares may be using cheaper materials to make the LCD's to save money. Other things is that since this seems to only be happening with the newer models, this could be a widespread problem and that maybe the company that makes LCD parts is making bad parts for some unknown reason.
I've been through this one once before, but...
Certain items (such as light bulbs, and possibly fluorescent tubes) are actually damaged each time they are turned on, but aren't damaged while they are left on.
If the energy cost (transport, manufacture, etc) of replacing the item is high enough, it may be more efficient to leave the item on to save it from damage.
If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
In my experience, for computers there is an initial power surge that is maybe 2-3x normal draw, and lasts anywhere from 20 seconds to a couple of minutes.
:-)
My workstation starts up with both fans running full power, then when the OS comes on line and realizes it has only one CPU (out of potential 2) and one graphics board (out of a potential 3) it switches the fans down to half speed (it may even switch one of them off altogether).
On higher end machines, the OS support getting actual fan rpm with a syscall
I was also interested to note that high CPU usage produces measurable extra power usage. On a dual-processor P3/733 system, each processor pulls an extra 10 watts under load.
Well, there is definitely more electrical activity in a busy system - for example, rather than just heartbeating and mostly idle, there will constant activity on the bus, between the I/O devices, within the CPU. The thing that really wastes power on my laptop is maintaining the 802.11b link while the machine isn't using the network - sometimes I'll pop the PCMCIA card out if I'm working, gets me up from just over 4 to just under 5 hours of battery.
Yep, but they are still worn if left on. A standard light bulb has life time of about 6000 hours and say it takes one hour off the life time every time it's turned on. If the light is continuously off for at least 2 hours by average it's more economical to turn off the light - especially if replacing it is expensive. Having special electronics to run the bulb with lower current when the light isn't needed might make some sense as it should worn less as the temperature drops with the current. That is, if the light is needed for short periods of time pretty often. Such electronics would often cost more than changing the bulb, though.
_________________________
Spelling and grammar mistakes left as an exercise for the reader.
I got an 8500 on my desk at work a couple months ago. Took it out of the box on Friday, set it up on the network, left it plugged in over the weekend (copying files) with the screen saver on. On Monday I came in and found the login screen being displayed (screensaver had turned off). From just one weekend of operation I have enough burn-in that I can read the Windows (I know, I know...) login prompt clearly. It's only getting worse, when watching DVDs I can see the task bar across the bottom of the screen, including all of the icons in the tool tray.
Comment removed based on user account deletion
Also, modern CRTs have assorted sleep modes. So whether or not to turn off a CRT depends on your usage patterns. For LCDs, I have no data.
While I have no data on LCDs, the key elements are the panel itself (which requires power to be set in an opaque mode, transparent shouldn't draw any) and one or more fluorescent lights. The lights are a big energy draw from my experience, which is why laptops have a brightness setting, and turn the screen off fairly quickly in power-saving modes. I typically get 1.5 to 2.5 hours of battery life if my brightness is set to be a lower level on battery and set to the lowest brightness. If I don't have it step down the level and have it on the highest brightness, I usually get around 0.75 to 1.25 hours.
This is one of the reasons OLEDs are being examined - removing the backlight (which is wasted when displaying darker colors) can reduce the total power usage.
Sure I'm paranoid, but am I paranoid enough?
I have had a 22" cinema display for four years (one of Apples oldest LCDs), running many hours a day (main machine) with no burn-in. I have a G4 Powerbook over a year old with no problems, and the two+ year old G4 powerbook it replaced (sold to a friend) has no problem either. I also know a few people with LCD iMacs, with no problems. Sounds like a dubious rumour to me.
We do see this problem with Apple flatscreens in the computer lab setting where I work, but there is a fairly simple solution. Turn off the flatscreen for a day or so, and the burn in goes away. The optical mice were too sensitive, and were turning off the screensavers every time someone sat down at a table. Don't know if this will fix the Dell laptops, but our Dell laptops (and Apple laptops) seem to be fine so far.
-Ryan
You will note that no matter what kind of program you run, it'll draw the same amount of power as long as the load % is the same. The exception might be an app that steps all over the cache, triggering memory to work hard.
:-)
Don't forget, you are talking first level cache, and can't be doing 3-D
graphics. Extensive use of the the floating point math co-processor also
adds watts.
I measured about a 20W difference/computer that was running SETI vs. blank-screen idle. The PC version had the graphics builtin to the screen saver too.
The height of SETI usage was the same summer we had rolling blackouts in
CA.
Nope -- 'work' as in applying a force to move electrons around qualifies as
work, I believe -- and 'work' done doesn't come with zero energy usage.
I think that was one of my rejected posts on slashdot at the time.
-l
We have Dell SX-260's here with flat panels, and every one of them does it. Couldn't give you a timescale, but they all do it intermittently. A reboot usually clears it, but this is still using energy save shutdowns after 5 mins inactivity...
One of the big drawbacks of LCD's is that the backlight has a fairly limited life. Usually 3-6 thousand hours. You shouldn't be using a screen saver, since the backlight is still on. You should use something that just shuts your screen off after X minutes.
:). I never used them. I just used a screen blanker, even with the old CRT's.
I never did understand screensavers...sure they keep burn in down, but your still displaying something on your screen, which does cause some burn in (just let it show the screen saver for 20 years!
>Having special electronics to run the bulb with lower current when the light isn't needed might make some sense as it should worn less as the temperature drops with the current... ...Such electronics would often cost more than changing the bulb, though.
Actually, it's very cheap. A standard diode in series with the bulb will reduce consumption by either 30% or 70% (I can't remember which, but I do know it isn't 50%). Diodes generally have expected lifetimes in the millions of hours, so they never get replaced.
The problem is that the cooler light bulbs run, the shorter their expected life span. That's why those "15 watt" bulbs you see are always designed so ruggedly -- they would have a very short (maybe under 1000 hours) lifetime otherwise.
Most light bulbs would last far longer than the standard life (perhaps as much as 10x, if not more) if left on forever. How many light bulbs have you seen die while they've been on for a while? All the ones I've seen die immediately when power is supplied.
But then again, that's just me...
If you could be told what you can see or read, then it follows that you could be told what to say or think - BoC
What happened to DPMS? Why don't you just enable that and be done with it?
The only real excuse for screen savers in this age of DPMS enabled monitors (and don't even try to say your LCD screen doesn't have it) is for locking the workstation while you go take a piss. So I say again, what's your screen doing on after 10 minutes idle anyway?
What sort of cheap, expensive garbage are these LCD manufacturer's trying to sell us here? It's not like LCD's are any cheaper than CRT's and the LCD's will eventually need their cold cathode lamps replaced...so what gives with this inferior tech? LCD's have the problem of reduced viewing angle, but are more compacet than CTR's, I would hope now-a-days that burn-in was a thing of the past? I have heard that other types of displays like expensive plasma tv/displays can get burn-in, quite severly too, so what's a person to do?, wait until flat plastic OLED's displays come out and hope that they have no burn-in too, or hope that OLED's are so cheap that if it craps out, throw it away and get an new one? What a mess, we get pathetic LCD's, pathetic hard drives (notice how warrenties have gone from 3 years to 1 year) and I don't know if anybody has done any statistics, but I suspect that processor chip life-spans and motherboard life-spans are not that great now-a-days (I recentlly had an expensive motherboard expire after about 3 years, over a decade ago, that would have not been the case, as most motherboards were built with some quality in mind)
You would want the backlight to turn off. This will protect the CCF lamps from burnout. It will also reduce heat and conserve energy.
I'd go on a Vegan diet but the delivery time from Vega is too long. --brownkitty
-- ;-)
Kuro5hin.org: where the good times never end.
He! I had a good example of that a couple weeks ago. I built a cluster of 12 PCs with 2 AMD Athlon 2400+ each, running OpenMosix. I had tested it in small chunks so I knew it could run. I moved everything over to the final destination, a 3000VA UPS, and invited my boss to come throw the switch.
It started perfectly and I started demonstrating the power of 30Gflops of AMD CPU working together: I started a script to run 24 instances of Seti@Home.
My finger was still on the [Enter] key when there was a loud Boom!, the UPS blew up and the whole room went dark. My boss: "Nice demo !"
Non-Linux Penguins ?
All I know is that the burn-in problem has been experienced on 2 Dells which both share the same WUXGA 15.4" displays, the Latitude D800 and Inspirion 8500. The ghost images appear only after about 2-3 of uninterrupted use and last about 1-2 days.
I'd have to say, if you're thinking of buying these machines, I'd make sure this problem is resolved first. At this time Dell is claiming that "No Problem Exists" if you call tech support.
Check out the Dell Forum Site for both of these laptops and you can see more info on the problem. It's be going on for about 2-3 months on the Latitude D800 and about 6 months for the Inspirion 8500.
...and it looks like dells are just cheap shit. whooda thunkit?
The original poster was not just talking about whether or not they were "high performance", but about their quality. So from the looks of it, you will be needing those identical machines, when they start crapping out on you, and you have to replace 'em.
I had a monitor at work that had the energy saving feature wherein, if there is no video signal, it turns off automatically. So, at the end of the day, I would start the power off sequence and leave, under the impression that the monitor would automatically shut off. They switched monitors on me and I had to manually turn off the monitor. Unfortunately, I'm sometimes in a rush to leave the office, and I forget to manually shut it off. The price I have to pay? Permanently burned in my screen are the words "Check Video Cable," burned in from a weekend of continous usage.
Screensavers doesn't prevent burn-ins. It just keeps the burn-in evenly distributed over the screen.
(Unless the burn-in is caused by a cumulating property increasing with the time the pixel's lit.
Ie. a dot has to reach a certain temperature in order to 'burn-in', otherwise no burn-in occurs. In this case using a screensaver would remedy the problem since the temperature of a dot never reaches the red line.)
what we used to do in the bad-old days of crt's was to display a white screen for 24h on maximum brightness.. makes the burnin evenly distributed. mught work for lcd's
a flat screen (finally) to replace my huge-ass CRT, this kinda crap comes up. Are there any decent flats with decent response time (for gaming) that don't cost an arm and a leg AND don't suffer this burn-in crap?
The prices for flats have gotten into the reasonable range but now they suck and aren't worth the price at all?
In Bushworld, they struggle to keep church and state separate in Iraq as they increasingly merge the two in America.
It is not affecting all of the Latitude series, just the ones with the 1920x1440 WUXGA widescreens. Mine has a burn of the Opera window that won't go away. I have my screen saver set for 3 min, but it doesn't matter if you use your computer all day. I tried moving my windows around, and all that did was put more burn marks all around. This can happen in under 2 hours of use, and will stay for days. I have a Dell 2000FP at home, and this never happens, even if left on for days with no screen saver, so I assume that it is just a really bad batch of screens. Apparantly though, Dell is replacing all the screens, so I will have to wait and see what transpires...
People who got burnin problems just need to buy a better display. I got an lcd here that works perfectly fine, got atleast 7,300 hours on it (2 years @ atleast 8hr a day).. never used a screensaver that actualy moves; I just have it display a steady world map when im gone.