Nvidia 9600m GT card 1-2 low level brightness backlight pulsates

[jjahshik32]

Anyone else have this issue? Its very strange when I'm using the 9400m card in any level brightness there is no flicker/pulsation of the backlighting BUT if I'm using the nvidia 9600m gt card on 1-2 low level notches the backlighting pulsates/flickers slightly.

Anyone else having the same issue? I guess an update is in need?

 

[smokedog]

Yes, me. I have requested a replacement. It happens with both graphic cards and very noticeable when the screen is cold.

https://forums.macrumors.com/threads/596727/

 

[the-bob]

i'm sporadically having the same problem w/ a mbp on both the 9400M and 9600M GT (512mb). I just got the system today so I haven't found a pattern about when the flickering begins. When it's happening, it's more obvious with low brightness settings. I've seen it occur with ac and battery power. I can make it stop by switching video cards so I'm guessing it may be a driver/software issue but I'd suspect to hear more people complaining about this.

 

[jgo78]

yep, same problem.

 

[jgo78]

from my continual investigation, I've come to the conclusion that it's not the screen itself. It some other internal hardware that's causing this issue. If my computer comes out of sleep/and or cold it pulses for about 10 minutes. But if just the screen is turned off for a long period but the computer is actually still on and then turn on the screen, there is no flicker at all.

 

[alphaod]

Okay I tested it and I don't seem to have the issue. I tried testing with the display cold as well. How do would you replicate the issue.

 

[jjahshik32]

from my continual investigation, I've come to the conclusion that it's not the screen itself. It some other internal hardware that's causing this issue. If my computer comes out of sleep/and or cold it pulses for about 10 minutes. But if just the screen is turned off for a long period but the computer is actually still on and then turn on the screen, there is no flicker at all.

On my mbp it doesnt matter if it comes out of sleep or its cold/hot or whatever condition, when its on 1-2 notches the backlight seems to flicker slightly but after a few minutes it stops flickering. But on any other brightness level theres no problem but it seems to be worse under windows on the 1-2 notches.

I'm ok with this issue since I never use it in 1-2 notches but hopefully a software update will fix this minor issue. Everything else is perfect though.

 

[antmo]

my 3rd try at getting an acceptable unibody mbp had this issue. after doing lots of experiments on being able to recreate it, i came to the following conclusions (keep in mind that this was on mine, but the problem being discussed has the exact same symptoms).

1. it happened using either graphics chip (9400 and 9600)
2. it wasn't noticable after about 3 or 4 display brightness notches up
3. physical temperature had no effect
4. corresponded to hard drive activity

i think the reason people think it happens when cold (more often) is because the apps they're running will access the hard drive more often at that time, in general. i found that if i started a new (larger footprint) app that had not been previously started since last reboot, it would happen every time. by larger footprint, i mean something that is fairly big and would tend to do a lot of hard drive activity when starting, which makes the flickering last longer and is therefore easier to see.

mjb

 

[jgo78]

my 3rd try at getting an acceptable unibody mbp had this issue. after doing lots of experiments on being able to recreate it, i came to the following conclusions (keep in mind that this was on mine, but the problem being discussed has the exact same symptoms).

1. it happened using either graphics chip (9400 and 9600)
2. it wasn't noticable after about 3 or 4 display brightness notches up
3. physical temperature had no effect
4. corresponded to hard drive activity

i think the reason people think it happens when cold (more often) is because the apps they're running will access the hard drive more often at that time, in general. i found that if i started a new (larger footprint) app that had not been previously started since last reboot, it would happen every time. by larger footprint, i mean something that is fairly big and would tend to do a lot of hard drive activity when starting, which makes the flickering last longer and is therefore easier to see.

mjb

are you keeping this one? or gonna try to get another.

 

[antmo]

are you keeping this one? or gonna try to get another.

i ended up buying a thinkpad w500 w/xp... it's funny, since i came to macs a handful of years ago from thinkpads

it's sort of a trade-off, since i get a matte high resolution screen in a 15-inch, relatively thin/light form factor, great build quality, same processor/memory/disk config as the mbp, ati firegl w/512mb and good customer service/warranty all for about 1k$ less, but i don't get to use macosx.

for me, better hardware specs for worse operating system was a compromise i was willing to make, especially since all the apps i use are available and perform well on both osx and xp and i'm not at all concerned with how my machine looks.

mjb