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Thread ID: 58366 2005-05-29 09:00:00 LCD Qwes+!0n jamesyboi (6579) Press F1
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359568 2005-05-29 09:00:00 hello.

www.pricespy.co.nz

I am interested in purchasing a 17" LCD monitor and ridding my sore eyes of my CRT monitor. There are a few different models of Cheimei lcd monitors for around $300-$370. I want a 8ms monitor so i can play games. and I want to be assured that it has no refresh rate....

my understanding of lcd monitors are that there is no refresh rate (eg 85hz) so it does not hurt your eyes. However, reading a review on the

ChiMei CMV CT-720D 17" 1280x1024 8ms DVI LCD it says

"This 17" TFT LCD monitor is capable of 1280x1024 pixels max. resolution. It features 0.264 mm dot pitch, 28-82 KHz horizontal scan range, 50-76 Hz vertical scan range, 8ms response time and features D-Sub/DVI-D signal inputs."

and on www.neoseeker.com
it says:

CMV CT-720D 17-inch 8ms TFT LCD
By Zachary Chan
Category : Monitor
Published by Vijay Anand on Friday, 28th January, 2005
Rating : 4 out of 5 stars (Most Value For Money Award)

Preset Timing Modes 640 x 480 @ 60, 72, 75Hz
800 x 600 @ 56, 60, 72, 75Hz
1024 x 768 @ 60, 70, 75Hz
1152 x 864 @ 75Hz
1280 x 1024 @ 60, 75Hz

!! does this mean that it has a refresh rate of up to 75hz on 1024x768?? if so im confused...thanks for any help
jamesyboi (6579)
359569 2005-05-29 10:01:00 Yes, vertical refresh rate affects LCDs differently than CRTs.
My LCD is running at 60 Hz and I can tell you that you'd go mad with flicker on a CRT at that refresh rate.

LCDs do have an optimum refresh rate for example mine likes 60 Hz at 1280 by 1024 with a DVI connection. They will however usually accept a range of values that they can accept (in other words you actually see an image).

To sum up: don't wory about the vertical refresh rate - those specs look typical.
gibler (49)
359570 2005-05-29 13:21:00 A CRT draws images by scanning the electron gun down the screen which excites phosphors just behind the glass, causing them to emit light. These do not glow for long (just a tiny fraction of a second) and need to be constantly re-excited. An LCD works differently, and the pixels are simply switched on and off.

60Hz means that the screen updates/refreshes 60 times per second. If there is no change to the LCD the pixels just stay as they were, constantly emitting light. If there is no change on a CRT screen the phosphors still need to be re-excited, so you can see how a flicker becomes visible at low refresh rates.

So on an LCD the refresh rate merely determines the maximum frame rate, and for all but the pickiest gamers, 60fps is fine. :)
Alexf2 (7807)
359571 2005-05-29 21:06:00 These do not glow for long (just a tiny fraction of a second) and need to be constantly re-excited.
For a moment there I thought you were talking about us men, and not visual displays :p
Myth (110)
359572 2005-05-29 21:58:00 So on an LCD the refresh rate merely determines the maximum frame rate, and for all but the pickiest gamers, 60fps is fine.
So if my laptop PC allows a higher refresh rate than 60, is it of any benefit to increase it?
Greg (193)
359573 2005-05-29 22:07:00 No, you should see no benefit.

And to correct a post above, the LCD pixels do not "emit light". The panels backlight is constant and passes through the LCD pixels which either pass the backlight through them (and it is filtered by their colour) or block the backlight.

But the backlight itself does not "flicker" at all so refresh rate is redundant in that term.
godfather (25)
359574 2005-05-29 23:38:00 thanks, i think i understand. im half retarded today (flu) jamesyboi (6579)
359575 2005-05-30 00:20:00 anyway. does anybody have a favourite?
www.pricespy.co.nz

theres a few different models of cheimei but i dont know which is best, the 8ms one is most expensive but it isn't the highest model no. anyway i have the flu and i can't be sure im typing this or im dreaming.....hehe...theres barney........ehem
jamesyboi (6579)
359576 2005-05-30 01:56:00 The link to the review of this monitor ends with:

"While the LCD price war rages, you will be hard pressed to find a better monitor at this price range now. Sadly, the flickering problem drags down the rating of an otherwise great monitor"

That would make me wary for a start and I also happened to be in someones office this morning with one of the very same monitors and it has one bright pixel already. (2wks old)
Looks like you might get what you pay for.
bartsdadhomer (80)
359577 2005-05-30 05:55:00 For a moment there I thought you were talking about us men, and not visual displays :p

But then if there's a short circuit do they get unpredictably excited? (might answer a few questions around here) :D
Shortcircuit (1666)
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