iMac G5 screen dimming, again

but this is different in that the entire screen dims evenly and it can be resolved by resetting things in the System Prefs.
Lorenzo Thurman wrote on :
I posted here a while ago about my screen alwasy starting up dimmed to the max. I thought it was fixed after I did the 10.3.8 upgrade, butala, after two successful reboots, the problem has returned and nothing seems to have ant affect. I've zapped PRAM and thrown out prefs to no avail. For the record, I believe there was a problem with half the screen dimming, but this is different in that the entire screen dims evenly and it can be resolved by resetting things in the System Prefs. I know othere have this problem, its all over the Apple Support pages, but no one seems to have an answer. Anyone knwo anything about this?
njbok replied on :

Anyone know anything about this?

No, but I have noticed it on mine as well. It brightens up by itself after a few minutes, though. A minor annoyance, but it does make one wonder, huh?

matt neuburg replied on :

Lorenzo Thurman lorenzo@redacted.invalid wrote:

I posted here a while ago about my screen alwasy starting up dimmed to the max. I thought it was fixed after I did the 10.3.8 upgrade, butala, after two successful reboots, the problem has returned and nothing seems to have ant affect. I've zapped PRAM and thrown out prefs to no avail. For the record, I believe there was a problem with half the screen dimming, but this is different in that the entire screen dims evenly and it can be resolved by resetting things in the System Prefs. I know othere have this problem, its all over the Apple Support pages, but no one seems to have an answer. Anyone knwo anything about this?

The only other suggestion I have is to go inside it and zap the SMU.

http://docs.info.apple.com/article.html?artnum=300908

This is what solved the top-half dimming problem for me. I realize it might not be the same problem but it's worth a go. m.

Lorenzo Thurman replied on :

In article 1gt27df.17zoe3h1tz9ekyN%matt@redacted.invalid, matt@redacted.invalid (matt neuburg) wrote:

Lorenzo Thurman lorenzo@redacted.invalid wrote:

I posted here a while ago about my screen alwasy starting up dimmed to the max. I thought it was fixed after I did the 10.3.8 upgrade, butala, after two successful reboots, the problem has returned and nothing seems to have ant affect. I've zapped PRAM and thrown out prefs to no avail. For the record, I believe there was a problem with half the screen dimming, but this is different in that the entire screen dims evenly and it can be resolved by resetting things in the System Prefs. I know othere have this problem, its all over the Apple Support pages, but no one seems to have an answer. Anyone knwo anything about this?

The only other suggestion I have is to go inside it and zap the SMU.

http://docs.info.apple.com/article.html?artnum=300908

This is what solved the top-half dimming problem for me. I realize it might not be the same problem but it's worth a go. m.

I got another reply from the Apple support pages, where a user suggests it might be a custom profile. I'll try it at home when I get there and see if makes a difference. How do I zap the SMU, I don't know about this one.

geech replied on :

"Lorenzo Thurman" lorenzo@redacted.invalid wrote in message news:lorenzo-831BC2.10204308032005@redacted.invalid

I got another reply from the Apple support pages, where a user suggests it might be a custom profile. I'll try it at home when I get there and see if makes a difference. How do I zap the SMU, I don't know about this one.

If you click on the link he posted, you will find out how to reset the SMU. Funny how that works out.

Lorenzo Thurman replied on :

In article d0l08501pqp@redacted.invalid, "geech" nod@redacted.invalid wrote:

"Lorenzo Thurman" lorenzo@redacted.invalid wrote in message news:lorenzo-831BC2.10204308032005@redacted.invalid

I got another reply from the Apple support pages, where a user suggests it might be a custom profile. I'll try it at home when I get there and see if makes a difference. How do I zap the SMU, I don't know about this one.

If you click on the link he posted, you will find out how to reset the SMU. Funny how that works out.

DUH

Lorenzo Thurman replied on :

In article lorenzo-0574FA.16190508032005@redacted.invalid, Lorenzo Thurman lorenzo@redacted.invalid wrote:

In article d0l08501pqp@redacted.invalid, "geech" nod@redacted.invalid wrote:

"Lorenzo Thurman" lorenzo@redacted.invalid wrote in message news:lorenzo-831BC2.10204308032005@redacted.invalid

I got another reply from the Apple support pages, where a user suggests it might be a custom profile. I'll try it at home when I get there and see if makes a difference. How do I zap the SMU, I don't know about this one.

If you click on the link he posted, you will find out how to reset the SMU. Funny how that works out.

DUH

So, I'm trying the simple thing first. I got a suggestion that the custom monitor profile might be the problem. So, I reset my iMac to the default "iMac" profile last night. This morning, it started up OK, with the brightness setting intact. I'll power it up again this evening and see what happens. I'm not averse to opening the box up, but if this fails I'll try resetting the SMU.