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gudrummer · 11:23 PM

Hi everybody!Just to check,has anyone noticed that the refresh rate of the Dell 2405 is 59Hz?I just bought the X800 and it shows this number...is it the same for everybody?

Mister Elf · Feb 3, 2006, 02:34 PM

All LCDs have the same refresh rate, 60Hz.

mduell · 08:51 PM

Originally Posted by Mister Elf

All LCDs have the same refresh rate, 60Hz.

Except when they don't.

gudrummer · Feb 3, 2006, 11:14 PM

Well,my ATI display shows 59...go figure...

tooki · Feb 7, 2006, 09:20 PM

Originally Posted by gudrummer

Hi everybody!Just to check,has anyone noticed that the refresh rate of the Dell 2405 is 59Hz?I just bought the X800 and it shows this number...is it the same for everybody?

Yes, that's normal. 60Hz is the maximum refresh rate possible at 1920x1200 resolution over single-link DVI.

Not that it matters, since LCDs don't flicker, no matter what the refresh rate. 60Hz is double the frame rate that humans can detect anyway.

tooki

wallinbl · Feb 7, 2006, 10:17 PM

Originally Posted by tooki

60Hz is double the frame rate that humans can detect anyway.

tooki

Set a CRT to 60Hz. Sit in front of it and then look to the left or the right such that the monitor is now in your peripheral vision. You will see the flicker. Bump it up to 85Hz or higher and you will stop noticing this. I can't use a CRT at less than 85Hz. I'll end up with a headache by the end of the day.

mikochu · Feb 8, 2006, 10:19 AM

My friend has a Dell 2405 on his PC and he complains about "input lag." Apparently his cursor lags. I've been looking at getting dual 20" Dells, single 24" Dell, or a single 23" ACD. The refreshrate on the ACDs are nowhere to be found. I hear people complaining about the 24" Dell...from it being too bright to crappy refresh rates. The 20" Dells have the same LCD as the iMac 20" and 20" ACD...but I kinda want native 1920x1200....lol. Decisions, decisions.

wallinbl · Feb 8, 2006, 10:23 AM

Originally Posted by mikochu

My friend has a Dell 2405 on his PC and he complains about "input lag." Apparently his cursor lags. I've been looking at getting dual 20" Dells, single 24" Dell, or a single 23" ACD. The refreshrate on the ACDs are nowhere to be found. I hear people complaining about the 24" Dell...from it being too bright to crappy refresh rates. The 20" Dells have the same LCD as the iMac 20" and 20" ACD...but I kinda want native 1920x1200....lol. Decisions, decisions.

I have dual 20" Dells (2001FPx2). I like having two screens better than one wide screen. 1600x1200x2 is pretty nice. The only drawback is that I bought them 9 months apart, and there have been slight changes to the model. It's mostly the same, but the pictures are slightly different (menu systems are different as well, but that's no biggie).

mduell · Feb 8, 2006, 03:12 PM

Originally Posted by mikochu

My friend has a Dell 2405 on his PC and he complains about "input lag." Apparently his cursor lags. I've been looking at getting dual 20" Dells, single 24" Dell, or a single 23" ACD. The refreshrate on the ACDs are nowhere to be found. I hear people complaining about the 24" Dell...from it being too bright to crappy refresh rates. The 20" Dells have the same LCD as the iMac 20" and 20" ACD...but I kinda want native 1920x1200....lol. Decisions, decisions.

Sounds more like a mouse problem than a display problem.
1920x1200 @ 60 fps is the maximum data rate for DVI, so the Dell 24" and Apple 23" must both have the same refresh rate.

mikochu · Feb 8, 2006, 05:14 PM

but Mark...how about all of those complaints about the 24" Dell dropping frames in FCP and such? Propaganda?

tooki · Feb 8, 2006, 05:34 PM

Originally Posted by wallinbl

Set a CRT to 60Hz. Sit in front of it and then look to the left or the right such that the monitor is now in your peripheral vision. You will see the flicker. Bump it up to 85Hz or higher and you will stop noticing this. I can't use a CRT at less than 85Hz. I'll end up with a headache by the end of the day.

Note that I said frame rate, not refresh rate. They do not mean the same thing, and they are not interchangeable. 30Hz is the more-or-less accepted threshold for humans to detect frame rate. (Cinemas, for example, flash each film frame twice: the frame rate is 24fps [or 24Hz], the refresh rate is 48Hz.)

I am very sensitive to refresh rate -- 60Hz is visibly flickery to me -- so I am well aware of how to look for it.

tooki

mikochu · Feb 8, 2006, 07:11 PM

qudrummer,

So...sans the 59hz issue...how do you like the 2405fpw? Do you notice any issues?

tooki · Feb 8, 2006, 08:05 PM

I know you didn't ask me, but I have been thrilled with my 2405FPW since I got it last Friday.

tooki

mduell · Feb 8, 2006, 08:54 PM

Originally Posted by mikochu

but Mark...how about all of those complaints about the 24" Dell dropping frames in FCP and such? Propaganda?

I wouldn't say it's propaganda; isn't there some "law" that says it's better to assume incompetence than malice?

I don't know all the details of the issue and the reports of the issue are inconsistent. I would guess it's video card related rather than display related, like the Mac mini video issue (noise on DVI, dark on VGA), where some displays are tolerant of an out-of-spec signal and others are not.

gudrummer · Feb 9, 2006, 10:35 AM

I haven't notice anything wrong,i'm still using FCP with no problems and playing Doom 3 from time to time,it was just funny when i noticed for the first time.Never had that with the 9650.

gudrummer · Feb 10, 2006, 12:04 AM

There's the proof.

crooner · Feb 10, 2006, 02:01 AM

I have two 2405s (with a 30" Apple Cinema Display in the middle - yes... display heaven) and they're great. Better than if I had gone with Apple 23"'ers.
FYI, the one connected to the second port on my 850 XT runs at 60 while the one on a Radeon 9200 runs at 59.9.
So there ya go...

gudrummer · Feb 10, 2006, 08:47 AM

I found the solution.On the advanced tab look for Advanced DFP and uncheck the first option(Enable ATI hardware Scaler on non-Apple panels).Working back on 60 Hz.

P · Feb 10, 2006, 10:51 AM

Originally Posted by wallinbl

Set a CRT to 60Hz. Sit in front of it and then look to the left or the right such that the monitor is now in your peripheral vision. You will see the flicker. Bump it up to 85Hz or higher and you will stop noticing this. I can't use a CRT at less than 85Hz. I'll end up with a headache by the end of the day.

As tooki explained, refresh rate is not the same as frame rate. CRTs work by having a beam light up the pixels one at a time. They keep the light for a while but slowly go dim. The higher the refresh rate, the shorter the time the pixel is allowed to go dim, the more even the light of the monitor and the less flicker.

LCDs don't work this way. The pixel stays on until switched off, so te flicker isn't there. For this reason, only the frame rate matters.

tooki · Feb 10, 2006, 11:22 AM

Originally Posted by gudrummer

I found the solution.On the advanced tab look for Advanced DFP and uncheck the first option(Enable ATI hardware Scaler on non-Apple panels).Working back on 60 Hz.

Why on earth would you want to disable the hardware scaler? Are you seeking lower performance on anything video?

59 vs 60Hz is probably just rounding error!! Either way, it's an immaterial difference, since it's a) above the threshold of human perception (and the difference too small to notice) and b) LCDs do not flicker: 59 vs 60Hz is, effectively just how often the image on the display can be changed. c) LCDs do not flicker.

tooki

gudrummer · 11:18 PM

So,should i just turn it on again?I was afraid of causing any problems to the screen with the 59 Hz refresh rate.

Ok,updated information.I was checking the image quality and if i leave the option on it screws up the horizontal lines.Playing Doom 3 and even scrolling the dock icons with the mouse with magnification on you an see the icon "breaking" in half,same with Doom 3 when turning left and right.I'll leave it off.

andreas_g4 · Feb 12, 2006, 11:07 AM

Originally Posted by crooner

I have two 2405s (with a 30" Apple Cinema Display in the middle - yes... display heaven) and they're great. Better than if I had gone with Apple 23"'ers.
FYI, the one connected to the second port on my 850 XT runs at 60 while the one on a Radeon 9200 runs at 59.9.
So there ya go...

Pictures, please. I wanna drool.