refresh rates for lcds

[Guest]

I thought the refresh rate only mattered with crts. Is this used for lcds as well?

[redwudz]

Not at least with the ones I use. I can set my laptop or my 15" LCD to 200Hz with no effect. It couldn't display that refresh rate anyway, but it accepts it. Apparently it just ignores everything but 60Hz. If I set it to 2048 X 1536 it magnifies the display to about 4X size, though. Apparently refresh rate is not adjustable with my LCD displays.

[guns1inger]

Refresh rates are measured differently for LCDs, and are dependent on the LCD itself, rather than the gfx card. LCDs are measured in ms (milliseconds) and are measured on the time it takes to redraw the entire display. A good speed is 12 - 16ms (lower is better). Anything slower than 16 begins to show ghosting in fast motion graphics (games, DVDs etc). It scares me that people buy LCD TVs with 20ms refresh rates.

[alsyed]

refresh rates in Hz or ms are reciprocal.

If you have a display rate of 60Hz, then its referesh time is 1/60 seconds = 16.6ms

70Hz = 14ms
80Hz = 12ms

see?

those 20ms refresh rates, are basically 50Hz, and they would be acceptable i guess in tv in pal country, where the field rates is 50 fields per second.