9400m Nvidia screen flicker after snow leopard install

Yeah, I hope it doesn't get cancelled, lol.

Hmm, I updated to 10.6.2, but the changelog didn't say anything about screen flickering. And the problem didn't go away either 😟

same problem here!!!

I MAY have found a workaround for this problem. I created a hot corner to put the screen to sleep. This doesn't put the computer to sleep, just the screen. When the screen starts to flicker badly, I invoke the hot corner to put the screen to sleep for about 5 seconds then move the mouse to restore it. The screen flicker stops until the computer is put to sleep again and then awakened. As soon as I repeat this step, I'm good.

My theory is that the RAM in the late 2008 MBP isn't fast enough to keep up with the 9400M, which causes the flicker. Putting the screen to sleep clears that section of RAM which, in essence, is similar to rebooting.

I can't swear that this is what's happening, but it makes sense. The 9600 has it's own VRAM so you don't see a problem with flickering.

Give it a shot and see if it works for you. I still think that Apple needs to address this problem, but I've had this problem for over a year and this is the first time I've come up with something that seems to quickly resolve the problem.

My screen did not flicker when running 10.5.x Leopard. However, when I did a fresh install of Snow Leopard followed by a migration of my 10.5.x system, that is when the flickering began. I checked my log files using "System Profiler" and I see nothing obviously wrong with my built-in display, nvidia 9400m or power management. The flickering is intermittent and causes the screen to blank for less than a sec.

Here is my active display info:

NVIDIA GeForce 9400M:

Chipset Model: NVIDIA GeForce 9400M
Type: GPU
Bus: PCI
VRAM (Total): 256 MB
Vendor: NVIDIA (0x10de)
Device ID: 0x0863
Revision ID: 0x00b1
ROM Revision: 3437
gMux Version: 1.7.3
Displays:
Color LCD:
Resolution: 1440 x 900
Pixel Depth: 32-Bit Color (ARGB8888)
Main Display: Yes
Mirror: Off
Online: Yes
Built-In: Yes
Display Connector:
Status: No Display Connected

My screen started flickering after leopard and my optical drive refused to write DVD +R after installing the v3 firmware. I took it in to be serviced under Apple care and they replaced the optical drive and the logic board. I still don't have it back yet because the replacement logic board also failed and we are waiting for another replacement. Thanks to MacResource (Huntsville,al) for their careful testing of replacement parts and checking their work before returning my machine. They are a great example of the excellent independent Mac dealers/stores.

Wow that is literally the exact same situation I'm in. DVD drive was burning +R and headphone out was stuck in optical out so I got a new motherboard and dvd drive courtesy of warranty. After the repairs I have this flickering on the 9400m now. It seems to be a software issue though.

I would like to add to this thread.

I have the same issue with screen flicker whilst running my MBP 5,1 in "better Battery life". The screen turns black for less than a second. Whilst in "Higher Performance" mode, I dont see any flicker at all. I am running Snow leopard (10.6.2)

Like the two, above posts, I have just received my MBP back from the service center, and had had the logic board replaced due to the optical port (headphone port) showing a red light. I hadn't had this problem previously. I am going to test cacheOut X as suggested above, and also see if logging into 9400 from 9600 cures the issue. I'll update with results.

newelley

Mine does this every once in a blue moon. I did a PRAM and SMC reset and haven't seen it since (knock on wood).

I've had the same exact problems as everyone posting here since installing Snow Leopard. I did all of the "fixes" (resetting pram, formatting and all that), and still had the flicker. Just got the laptop back after a Logic Board replacement, and so far so good. Hopefully it stays this way! and hopefully all of you can get this solved, cause as people have said before, having this issue on a $2,000+ machine is just unacceptable.

10.6.3 did not fix this issue at all.

I too am experiencing the flashing screen, although it's pretty intermittent. It only started upon upgrading to Snow Leopard, and continues with 10.6.3. It only occurs when using the 9400, as folks have noted.

This is only the latest problem with the NVIDIA chip. The 9400M on my MacBook Pro 5,1 has been basically unusable since I got it. Under Leopard, I'd have hard crashes where the screen would go black or stripey, the MBP would emit an extremely loud screeching noise, and I'd have to manually power-cycle. So I was mostly using the 9600 anyway.

Under 10.6, I haven't had the hard crashes any more with the 9400, but the flickering is there. For me it is only the top 15-20% of the screen that flashes black. I have a hard time believing these two issues are unrelated, but I don't know whether it's a hardware or driver issue.

So, it's back to the 9600 for me unless I'm on a plane. I've never had a problem with it except for the short battery life.

I'm not sure if the problem I have is the same but it seems to be similar. I've noticed after installing Snow leopard that white flickers (like static lines around 2 - 3 inches long) occur at random places at the left side of my MBP display. This occurs regardless on both vid chips for me.

I find that it only occurs when the screen is black and so i downloaded Pixel check and tested all the color settings on it. The flickers of static lines only occur when all my pixels are on (black) and it only occurs at the top-left and bottom-left of the screen. The recent firmware update didn't fix my issue either 😟. I've read similar problems with the iMac 27", but has any MBP users experienced this problem that I have as well?

Hope I had post this up correctly! Many thanks.

I had a persistent problem with screen flicker when using the 9400M chip (energy saving mode) on my late 2008 MacBook Pro. I tried all the suggested fixes on the forums. The AppleStore replaced the logic board and the problem remained. I've been forced to run using the discrete 9600GT chip to prevent the flicker. The problem finally seems to have gone away after replacing my hard drive with a Samsung SSD drive. I've been running a few weeks on the 9400M with no flicker and I saw screen flicker immediately before replacing the drive. I had the flicker problem through three hard drives. A 250 GB Fujitsu (that came with it), a 500 GB 5400 RPM Seagate, and a 500 GB 7200 RPM Seagate. I'm a road warrior and frequently wear out my hard drives carting it around so much. I was surprised to see the problem go away after upgrading to the SSD. I frequently run on the 9400M chip and live with the flicker if I want more battery life. Hope this helps others that have been unable to find the source of their problem.