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B.Lehman

macrumors newbie
Original poster
Dec 5, 2004
15
0
york, pa
I have a 1.33/15" Al Powerbook that I bought about 6 weeks ago as a refurb. I'm noticing that when I connect it to either of the 19" CRTs I have, the video display looks almost like it has JPEG artifacts (slightly fuzzy, and splotchy for lack of a better way to put it). I've tried both monitors that I have (and they look fine when connected to my xp box), and also tried a different DVI to VGA adapter. I'm guessing that if there is a problem here, it must be in the DVI out on the powerbook (the PB LCD screen looks fine). Can any powerbook owners comment on the quality of video display when using an external monitor?

This is really kind of bothersome to me as I'd really like to be able to use an external monitor when at my desk and be able to pick up some extra screen real estate. I was also considering buying a Cinema display, but really want to figure out what is going on here first.

-- Brad
 

G5orbust

macrumors 65816
Jun 14, 2002
1,309
0
B.Lehman said:
I have a 1.33/15" Al Powerbook that I bought about 6 weeks ago as a refurb. I'm noticing that when I connect it to either of the 19" CRTs I have, the video display looks almost like it has JPEG artifacts (slightly fuzzy, and splotchy for lack of a better way to put it). I've tried both monitors that I have (and they look fine when connected to my xp box), and also tried a different DVI to VGA adapter. I'm guessing that if there is a problem here, it must be in the DVI out on the powerbook (the PB LCD screen looks fine). Can any powerbook owners comment on the quality of video display when using an external monitor?

This is really kind of bothersome to me as I'd really like to be able to use an external monitor when at my desk and be able to pick up some extra screen real estate. I was also considering buying a Cinema display, but really want to figure out what is going on here first.

-- Brad


Artifacting is a symptom of GPU overheating. You may want to call Apple and have them check it out.
 

killuminati

macrumors 68020
Dec 6, 2004
2,404
0
I'v used my 15" pb with a dell monitor on numerous occasions and never had any problems.
 

B.Lehman

macrumors newbie
Original poster
Dec 5, 2004
15
0
york, pa
G5orbust said:
Artifacting is a symptom of GPU overheating. You may want to call Apple and have them check it out.

That seems sort of weird. The machine doesn't really seem that hot, and like I said... the PB LCD looks fine at the same time that I am noticing the weirdness on the CRT screen.

I'm not sure that I am describing the symptom very well at all. Basically, at a quick glance, you might not notice a problem at all. If you look closely though, you'll notice things like black text on a white page having a sort of grey halo effect, and areas where there should be a smooth gradation show a sort of mottled effect. For lack of a better way to put it, it seems to me much like how a JPEG image looks if you set the compression too high, and you start to lose quality.

At any rate, it kind of sounds like a call to apple is in my future. I do have an apple store about 45 minutes away from me. Would I be better off taking it in and trying to get one of the geniuses to look at it?

-- Brad
 

cfd

macrumors member
Nov 29, 2004
73
0
Are you using video mirroring or extented desktop? If you are using video mirroring, all you will get is the 1280 X 854 resolution of the laptop. If you use extended desktop, you will be able to get the maximum resolutiom of the CRT. All of this is adjusted is the display preferences.
 

B.Lehman

macrumors newbie
Original poster
Dec 5, 2004
15
0
york, pa
cfd said:
Are you using video mirroring or extented desktop? If you are using video mirroring, all you will get is the 1280 X 854 resolution of the laptop. If you use extended desktop, you will be able to get the maximum resolutiom of the CRT. All of this is adjusted is the display preferences.

I was using both the extended desktop, and the clamshell mode of the powerbook. I noticed the anomaly at 1600 x 1200 (my preferred resolution for the monitor) and 1280 x 1024 (just messing around to see if there was any difference) while in clamshell mode. Any mode that I ran the display in resulted in the same artifacting.

-- Brad
 

cfd

macrumors member
Nov 29, 2004
73
0
Hmmm. The only other fix I can think of is changing the refresh rate if that is possible.
There is also a long thread in the Apple Discussion boards which might be the issue you are having.
 

B.Lehman

macrumors newbie
Original poster
Dec 5, 2004
15
0
york, pa
cfd said:
Hmmm. The only other fix I can think of is changing the refresh rate if that is possible.
There is also a long thread in the Apple Discussion boards which might be the issue you are having.

Well, that sounds like the issue alright :(

I guess I'll just have to call apple tomorrow and see what they say about it.

Thanks for the help folks. I'll update this thread when I get some feedback on the issue from apple.

-- Brad
 

Mechcozmo

macrumors 603
Jul 17, 2004
5,215
2
Download Temperature Monitor from VersionTracker. It shows on my 12" PowerBook Rev. C the GPU's temperature. Might be worth downloading. It is free, so might as well.
 

B.Lehman

macrumors newbie
Original poster
Dec 5, 2004
15
0
york, pa
Alright...

I just got off the phone with Apple. After going through the normal series of resets (PRAM, nv-ram, open firmware, PMU, etc.), there is still no improvement. Their suggestion at this point is to go to the closest apple store (about an hour away for me), and have one of the geniuses take a look at the machine. Short of that, the rep I spoke to said that it would be a trip back to the mothership for my powerbook. I can't say that I feel really good about that one.

For anyone that didn't read the apple support thread that was linked further up, it looks like the logic board replacement route doesn't really change anything. It also appears that this issue is totally related to using a VGA interface monitor. In the other thread, the people who were having troubles with VGA monitors could plug the same machine into a Cinema (or other DVI interface) display and get good video. Maybe I should beg for a good deal on that 23" Cinema that I've been wanting while I'm at the apple store.

-- Brad
 

mischief

macrumors 68030
Aug 1, 2001
2,921
1
Santa Cruz Ca
B.Lehman said:
Alright...

(snip)
It also appears that this issue is totally related to using a VGA interface monitor. In the other thread, the people who were having troubles with VGA monitors could plug the same machine into a Cinema (or other DVI interface) display and get good video. Maybe I should beg for a good deal on that 23" Cinema that I've been wanting while I'm at the apple store.

I had 2 thoughts...

1: The anomalies you're describing are similar to what's seen when the settings for a monitor default to "Thousands of colours" in the event that the GPU can't agree with the monitor's logic board over either resolution, refresh rate or both.

1a: In the event that your GPU is, indeed overheating it would not necessarily be detectable to the touch as it could be caused by it's heat-sink coming loose or a chip/graphics board fault.

2: Costco has some relatively nice generic 19" LCD's with DVI for about $400.00. Best price I've seen with DVI and has acceptable image quality with good contrast. Note: I'm not producing anything for offset printing or requiring pro-level color matching.
 

emw

macrumors G4
Aug 2, 2004
11,172
0
B.Lehman said:
Alright...

I just got off the phone with Apple. After going through the normal series of resets (PRAM, nv-ram, open firmware, PMU, etc.), there is still no improvement. Their suggestion at this point is to go to the closest apple store (about an hour away for me), and have one of the geniuses take a look at the machine. Short of that, the rep I spoke to said that it would be a trip back to the mothership for my powerbook. I can't say that I feel really good about that one.

For anyone that didn't read the apple support thread that was linked further up, it looks like the logic board replacement route doesn't really change anything. It also appears that this issue is totally related to using a VGA interface monitor. In the other thread, the people who were having troubles with VGA monitors could plug the same machine into a Cinema (or other DVI interface) display and get good video. Maybe I should beg for a good deal on that 23" Cinema that I've been wanting while I'm at the apple store.

-- Brad
One thing to look at would be to insure that you are running at the optimal resolution and color depth of the monitors to which you are connecting, not just your favorite resolution. I agree with mischief that the "blotchiness" sounds like a gradient issue that occurs at either resolution mismatches or too low of a color setting.

In terms of the fonts - you may want to check your "font smoothing style" in the Appearance preferences pane to make sure it's set for CRT.
 

B.Lehman

macrumors newbie
Original poster
Dec 5, 2004
15
0
york, pa
emw said:
One thing to look at would be to insure that you are running at the optimal resolution and color depth of the monitors to which you are connecting, not just your favorite resolution. I agree with mischief that the "blotchiness" sounds like a gradient issue that occurs at either resolution mismatches or too low of a color setting.

In terms of the fonts - you may want to check your "font smoothing style" in the Appearance preferences pane to make sure it's set for CRT.

Thanks for the help.

These symptoms appear at ALL resolutions and refresh rates. They are somewhat less severe at certain res/refresh settings, but never disappear. Take a look at the apple forum thread linked further up... this is exactly the problem I am having. When I created the test document mentioned in that thread, I get the exact same results.

This may not be a problem for some people, but it is an absolute disaster for me. It is very difficult to do graphic work when you are getting muddy text display, and ghost images all over the place.
 
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