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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 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.
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
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"
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"
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.
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.
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.
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.
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
They already are...again.
A firewall can not protect you from yourself. Turn off what you do not need. Do not use the firewall to do your work.
"Sounds like a new Dell Profit Center to me...What with a new $80 shipping and handling charge for warranty repairs."
Is this a recent development? Back in December I bought a Dell laptop. In January, the screen went out. I called Dell, and two days later I recieved a box to ship the laptop back to Dell. I sent it back out on a Friday and on Monday I had a working laptop. No fees no nothin.
Are you just being sarcastic?
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
It's called Lexan. Measure your monitor, go to Home Depot or Lowes and buy a piece. The store will cut it for free. It's very thin and you can keep it in your laptop bag or somehow affix it to your screen casing.
It's not stupid. It's advanced.
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.
Isn't After Dark supposed to be released for OS X any day now?
Never hit your grandmother with a shovel, for it leaves a bad impression on her mind...
Isn't After Dark supposed to be released for OS X any day now?
Well I'll be damned. Too bad it doesn't have any of the classics, and the reviews are generally negative, it seems.
--Dan
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
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!