Dead pixels?

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One of the things which is holding me back from odering either a NEC or a Viewsonic flat screen is the issue of dead pixels.

-what percentage of flat screens have at least one dead pixel?

-what retailers will take a monitor back / exchange it if it has one or more dead pixels? (rather than saying that 1-10 dead pixels is "acceptable" because I think having an always-on pixel would drive me crazy)

-do pixels tend to go bad over time?

Unfortunately, I'll have to order this over the Web or via mail rather than hand-selecting a good one from a store.
 

flamethrower205

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Assuming you don;t press on the screen, the # of dead pixels won't increase. PS: Viewsonic considers up to 5 dead lixels to be fine- although I would go mad if I were to have a dead pixel as well.
 
G

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just as I write this I'm sitting on a notebook with one dead pixel almost in the center of the screen. it's been there from the first day I got it. first I thought 'Oh [-peep-], I want a replacement' but that didn't work as I was told that up to 3 dead pixels have to be tolerated. Oh thank you very much!

anyway. I hardly notice that pixel anymore. it's not as much of an anoyance as I thought in the first place. I can live with it quite happily. and I do watch movies on this machine and do graphic stuff.

pixels usually don't go bad over time. but the display are fragile and if not handled carefully they can be damaged but that should be common sense.
what's more likely, that the wiring to the display gets damaged (even under proper use) and that it results in lost pixels (whole blocks of pixels usually). the wiring is under quite some strain by the frequent open/close off the display of a notebook. it happend on my old ASUS one.
TFT flat-screen monitors should not suffer from that though.

respect!
 

flamethrower205

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I was reading up on dead pixels, and here's some more info, which you may find very useful. First let me exxplain that per each pixel in the screen (you get the number of pixels by multiplying the pixels by lines (ex: 1024x768)). Each pixel consists of three pels, one red, another green, and another blue. Therefore, once you have the number of pixels, you multiply that by 3 and you have the number of pels. Typically, there is a 1:1,000,000 chance that there will be a defective pel. Therefore, there is a chance that there will be defective pels/pixels, but if there are, there shouldn't be that many. Here are the number of defective pixels/pels allowed by each company for some more commom displays:
Iiyama 38b 13 pels or 3 consecutive spots
Mitsubishi LCD50 6 or 3 adjacent
Philips 151AX replace at 10 or more
Samsung 520TFT 4 bright, 7 dark, or 2 adjacent
Seceptre BT15 18
CTX 745 10
HP 1024 1 pixel, 15 pels on, 18 pels off
NEC LCD400 Depends on the number / location
Sceptre FT15 9
ViewSonic VP140 7, 2 if adjacent
Of course there always is the option of returning the LCd even if there is 1 defective pixel- chances are you will get something that is better ("perfect" LCD's are yeilded, it's just that if only "perfect" LCD's were sold, the prices would be crazy.)
Hope this helps
 
G

Guest

Guest
Wow what a lot of research you must have done to come up with that "list" of Manufacturers and how many dead pixels they consider to be "defective." How nice of you to share that with everyone!

I was glad to see all that info. compiled but depressed after reading it. This is one of the things keeping me from buying a flat panel. I guess I'm picky but I can see myself simply sitting & staring at that one dead pixel, definately not being able to ignore it!!

Do you have a flat panel?

Barb

JerseyGirl
 

flamethrower205

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My first flat panel was a VP150m for Viewsonic. All I can say is it sucked, but b/c of issues with color ramps. As for dead pixels, there was no problem there- remember, man LCD's produced don't have dead pixels. Currently, I am going to buy the L371 from Eizo b/c it could be the one. That company specifically I have noticed has some of teh lowest defective pixels in the industry.
If dead pixels are one reason you don't want to buy an LCD, I have to say that is a bad reason. What you can always do is purchase our LCd from a computer store close by that will take it back within 30 days, no questions asked. This way, you can keep trading LCD's till you get the one you want- they may even let you take a look at thge ones they have in stock, and let you choose which one you want.
 
G

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fully agreed with Flamethrower.

check the dispaly in store. let them run it so you can see easily if it got dead pixels. take the one that doesn't.
if you're not a 3D-gamer with very fast on screen action like Quake & Co your eyes will thank you for using a good quality TFT.

respect!
 

killall

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you learn to live with them just like you learn to live with the horizontal lines on flatscreens... you just dont notice them any more... your eyes make ammends just like the yellow light coming in from the light bulbs is turned white by your eyes...

you do not strengthen the weak by weakening the strong
 
G

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Let me give you my take on the dead pixel disscusion.

I just got a new computer, and decided to spend some big bucks for a nice monitor. At the store I picked out the Sony A400/L, a nice 19" FD Triniton. I got it home, hooked it up, and immediately noticed that the top of the screen had a substantial bow to it. Since you can only adjust the sides, there was not much I could do, so I exchanged it for a different model. This one had a problems with uneven middle left section - it sortof drooped in the middle. Needless to say I was getting a little tired of driving back and forth to the store so my thoughts turned to a flat screen...

I exchanged the Sony CRT for a Samsung 760V TFT 17" Flat Panel, and never looked back. The screen is perfectly uniform, bright, and sharp as it can be. Now to the issue of dead pixels.

My screen has 3 dead pixels, two on and one off. At first I thought about exchanging it again, but I decided to check display models at a few stores to make sure that I could actually find a perfect one. No such luck. EVERY 17" Flat Panel that I looked at had at least 2 dead pixels. So I took a drastic step and actually decided to live with those dead pixels. Two months later I couldn't be happier - I don't notice them at all, and the advantages of a TFT vs CRT screen go far beyond size and weight. Unless all you do is fast 3D games, a TFT monitor is really one of the best investments you can make.

Hope this helps.
 

flamethrower205

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Well from teh calculation I made earlier it shows that with all probability there will some dead pixels on a 17". 15" one are a different story. There are a few LCD's on teh market which are good for fast motion video, as well as have top picture quality. The Eizo L371 is one of them, and from looking at the specs of teh compaq tft5030, it looks very impressive.

When I rule the world, Apple will only mean the fruit.
 
G

Guest

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Dead pixels are the result of a defective driver chip. I use to work at a place that had a large complex machine that was used to replace the driver chips for dead pixel.

Todays displays are very tolerent to being touched.

Later.
Patrick



Take Care.
What the heck was that all about!
 

flamethrower205

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Are u planning on buying it? Personally, I'm not impressed. Check out the compaq TFT5030 at http://www.compaq.com/products/monitors/flatpanel/tft5030.html. I prefer LCd's w/ a higher cointrast ratio, and what is the response time of teh KDS. Otherwise, I like teh design of teh monitor.

Your brain: PC
You brain on drugs: Mac