Odd issues with Al 20" iMac

[SpookTheHamster]

I bought a new iMac a little while ago, and I've noticed a couple of odd issues with it.

The first is that some shades of certain colours appear to be moving slightly. They have a wavy effect passing over them, and it's quite distracting. The main place I notice this is on my background. Try setting the attached image as your background and look in the bottom right corner to see the effect.

The other is that it just seems noisier than my white C2D iMac, the hard disk is quite loud.

 

[TBi]

The screen in the new AL iMac's is only 18bit so it has to dither the colours (read: flickers between two colours to make it look like a colour in between them) which leads to this kind of shimmering/noise. It usually switches at such a high rate that you don't notice it.

Then again i could be wrong and your screen could just be damaged.

 

[SpookTheHamster]

I don't recall noticing this on my old white C2D iMac, have they moved to a lower quality screen?

 

[TBi]

I don't recall noticing this on my old white C2D iMac, have they moved to a lower quality screen?

Yup, the old one was full 24-bit.

 

[r-sparks]

The other is that it just seems noisier than my white C2D iMac, the hard disk is quite loud.

Was your older white iMac a 20in model? I've had a 20in white iMac since late 2006 and it's far from "whisper quiet", as other people say. In fact, it's noticeably blowy and rumbly, although nowhere near as bad as a standard PC.

I ended-up swapping out the noisy Seagate hard disk for another model. While researching the problem, I noticed that most reports of "whisper quiet" iMacs came from 17in owners. In fact, it seemed to me that most people either bought 17 or 24in models. I'm not sure if detailed sales figures are available but I wouldn't be surprised if the 20in model was the least popular.

 

[SpookTheHamster]

Yes, my old iMac was a 17 and it was silent.

The dithering is really irritating, it's all I see when I play games. One thing I have noticed about it is that it only shows up in Windows.

Another problem I noticed is that when I play a sound in Windows, it is accompanied by some very strange noises. It sounds like a CD spinning up and down with wind howling in the background. This even happens if I mute the volume, and it's always at a fixed volume, so when the volume is at one bar it's very over powering.

edit: Is the screen on the 24" still 18-bit?

 

[DemNoir]

Apple makes nice products but they have the strangest customers in the technology world.

 

[theanimala]

Yes, my old iMac was a 17 and it was silent.

The dithering is really irritating, it's all I see when I play games. One thing I have noticed about it is that it only shows up in Windows.

Another problem I noticed is that when I play a sound in Windows, it is accompanied by some very strange noises. It sounds like a CD spinning up and down with wind howling in the background. This even happens if I mute the volume, and it's always at a fixed volume, so when the volume is at one bar it's very over powering.

edit: Is the screen on the 24" still 18-bit?

No, the 24" is a 24-bit screen, one bit per inch.

 

[TBi]

No, the 24" is a 24-bit screen, one bit per inch.

12-bits per foot

Does that make the 20" 20 bit and the 17" 17 bit though?

OMG the 13.3" MB only has a 13.3 bit screen!

 

[docprego]

I bought a new iMac a little while ago, and I've noticed a couple of odd issues with it.

The first is that some shades of certain colours appear to be moving slightly. They have a wavy effect passing over them, and it's quite distracting. The main place I notice this is on my background. Try setting the attached image as your background and look in the bottom right corner to see the effect.

The other is that it just seems noisier than my white C2D iMac, the hard disk is quite loud.

The hard disk should barely be audible, some clicking is normal.

 

[JBat]

Apple makes nice products but they have the strangest customers in the technology world.

Lol!

 

[redraidermacman]

I have had a 20" al imac for almost a month and it is whisper quiet, seems like something may be up with yours.....not sure, and whisper to me may not be to you, but i can BARELY hear a little hum from the fans inside...in fact my wifes macbook is actually louder than my imac