Display freezing - NVChannel(GL): Graphics channel exception

I've been following this tread for a week or two. I also have a MacBookPro3,1 with NVIDIA GeForce 8600M GT that started to freeze after installing the Leopard Graphics Update. Today I did an archive and restore back to 10.5.1, then updated everything except LGU. The problems are gone! Everything seems to be working fine again.

Those of you who are going the hardware repair route, please keep us informed of how that turns out for you.

Have used my MBP a lot in the week since I did the archive & install & all updates except LGU. Everything is fine.

I have been following the related thread at Mactopia:

http://www.officeformac.com/ProductForums/Excel/822

Microsoft reported this "bug" to Apple about a week ago. On March 28th, Pat McMillan of the Mac Business Unit wrote that "We've actually now received confirmation from Apple that this is caused by a bug in one of their drivers..."

I'd suspect a hardware fault, have you run the tests from Install DVD1 (hold d at Boot) to see if it shows anything ?

I'm having the same problem with mine, and the hardware test said there were no problems. Mine only happens when playing games. I think it is a driver issue, since the same games and pretty much everything else works in Windows in Boot Camp. This is an OpenGL problem in OS X.

I'm having the same issue when I play Mac OS X games. Doesn't seem to be an overheat or hardware issue because the same games play fine on windows. I don't understand what is taking so long though.

Same here! I get the lock only while playing games. I have one entry of the NVChannel timeout. I ran the extended hardware diagnostics and it came back peachy. A fix would be appreciated. 🙂

I am having the same issue as well. My screen gives me strange behaviors and soon after locks up. The only fix I have discovered so far, is using a second monitor. I was using on the laptop at home and was repeatedly getting a lock up, but I connect to two monitors at work and no problem. I was certain it was a network issue, but it has proven to be the second monitor plugged into the DVI port that has "fixed" my issue. However, this does not bode well for a "mobile" killer laptop. Any suggested fixes on this manner would be nice for me as well.

Same problem here, with or with-out external monitor. Will apple fix the drivers or is this a hardware error?


From system log:

Oct 10 23:49:59 zoom kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 10 23:49:59 zoom kernel[0]: 0000000c
Oct 10 23:49:59 zoom kernel[0]: 00200000 00005039 00000474 00000000
Oct 10 23:49:59 zoom kernel[0]: 00000484 00000100 00000000 00000003
Oct 10 23:49:59 zoom kernel[0]: 00000000 00000000 00000141
Oct 10 23:49:59 zoom kernel[0]: ath rxproc: NO RX Packets for 5 contiguous interrupts first DS Vaddr 0x63112000 Paddr 0x193b8000
Oct 10 23:49:59 zoom kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0x6 = Fifo: Parse Error
Oct 10 23:49:59 zoom kernel[0]: 0000000b
Oct 10 23:49:59 zoom kernel[0]: ath rxproc: NO RX Packets for 5 contiguous interrupts first DS Vaddr 0x63112000 Paddr 0x193b8000
Oct 10 23:49:59 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last cl
ip position (148b,5ec)->(148e,24ed).
Oct 10 23:49:59 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - adjusting clipped position to (148e,5ec)
Oct 10 23:50:03 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last cl
ip position (1495,27d8)->(1497,2ea).
Oct 10 23:50:03 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - adjusting clipped position to (1496,27d8)
Oct 10 23:50:06 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last cl
ip position (149f,20be)->(14a1,3366).
Oct 10 23:50:06 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - adjusting clipped position to (14a1,20be)
Oct 10 23:50:07 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - Error: attempting to clip to a position more than one buffer ahead of last cl
ip position (14a2,1f66)->(14a4,200d).
Oct 10 23:50:07 zoom kernel[0]: IOAudioStream[0x7449a00]::clipIfNecessary() - adjusting clipped position to (14a4,1f66)
Oct 10 23:50:08 zoom kernel[0]: ath rxproc: NO RX Packets for 5 contiguous interrupts first DS Vaddr 0x63112000 Paddr 0x193b8000
Oct 10 23:50:26 zoom kernel[0]: ath rxproc: NO RX Packets for 5 contiguous interrupts first DS Vaddr 0x63112000 Paddr 0x193b8000
Oct 10 23:50:26 zoom kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 10 23:50:26 zoom kernel[0]: 0000000c
Oct 10 23:50:26 zoom kernel[0]: 00200000 00005039 00000474 00000000
Oct 10 23:50:26 zoom kernel[0]: 00000484 00000100 00000000 00000003
Oct 10 23:50:26 zoom kernel[0]: 00000000 00000000 00000041
Oct 10 23:50:26 zoom kernel[0]: 0000000c
Oct 10 23:50:26 zoom kernel[0]: 00200000 00005039 00000474 00000000
Oct 10 23:50:26 zoom kernel[0]: 00000484 00000100 00000000 00000003
Oct 10 23:50:26 zoom kernel[0]: 00000000 00000000 00000041
Oct 10 23:50:26 zoom kernel[0]: ath rxproc: NO RX Packets for 5 contiguous interrupts first DS Vaddr 0x63112000 Paddr 0x193b8000
Oct 10 23:50:26 zoom kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 10 23:50:26 zoom kernel[0]: 0000000c
Oct 10 23:50:26 zoom kernel[0]: 00200000 00005039 00000470 00000000
Oct 10 23:50:26 zoom kernel[0]: 00000484 00000100 00000000 00000003
Oct 10 23:50:26 zoom kernel[0]: 00000000 00000000 00000000

I see the same thing in my console log after a display freeze up. Both times it happened, I had iTunes playing an album -- which kept on playing. The first time, it happened when I inserted a CD (another song was playing). The second time, I was starting VMWare (it was not even running the first time through).

Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 19 12:26:55 xxxx-computer kernel[0]: NVChannel(GL): Graphics channel timeout!

[Note: I replaced my computer's name (which is my name) with xxxx in the log above]
- Jim

Message was edited by: CT-JFK

Message was edited by: CT-JFK

I have exactly the same problem. The display freezes, mouse freezes, and I cannot other thing but to restart the machine. I have no clue what's going on. I don't play games. This (MacBook Pro 2.4) is my work computer. As non-Apple software I am running Matlab (from Mathworks), which runs under X11. No more other 3D intensive stuff.

My Log:

Oct 22 16:13:20 Teide kernel[0]: NVChannel(GL): Graphics channel timeout!
Oct 22 16:14:19 localhost kernel[0]: hi mem tramps at 0xffe00000
Oct 22 16:14:19 localhost kernel[0]: PAE enabled
...

My brand new MacBook Pro is doing the same:
Oct 26 13:04:49 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001
Oct 26 13:05:06 COMPUTERNAME kernel[0]: NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0xd = GR: SW Notify Error
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 0000000c
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00200000 00005097 0000047c 00000000
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000486 000015e0 00000000 00000003
Oct 26 13:05:06 COMPUTERNAME kernel[0]: 00000000 00000000 01bf8001


Only seems to happen when I run FinalCut Pro 6.01 or iShell - editing/running (admittedly very large) video (2000x750 pixels) across two 24" displays via a Matrox Digital Dual Head to Go at 3840x1200 resolution. Other non-intensive apps seem fine (eg mail, safari etc)

Completely freezes and I can't even force quit - have to manually power-off and on again. Haven't tried Motion yet, but I suspect this will crash too.

Model Name: MacBook Pro
Model Identifier: MacBookPro3,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.4 GHz
Number Of Processors: 1
Total Number Of Cores: 2
L2 Cache (per processor): 4 MB
Memory: 4 GB
Bus Speed: 800 MHz
Boot ROM Version: MBP31.0070.B02
SMC Version: 1.18f2
Serial Number: W874203DXA9
Sudden Motion Sensor:
State: Enabled

My MacBook Pro 15" (Santa Rosa chipset) freezes occasionally too.

At first I thought it was a problem when connecting an external display, but it happens even when I have not hooked anything to the DVI port. The freezes occur in plain OS X (not a game or anything special) and I think I have traced the issue to something related to the graphics card. Each time the system freezes, I have the following error in the system.log

Jan 15 16:27:40 Suuuju kernel[0]: NVChannel(GL): Graphics channel timeout!

The MacBook passes the Apple Hardware Test in both the default setting and the extended test without a problem. I also tried MemTest in a single-user environment and the Mac passes that too.

The problem could be heat-related in some way because when the MacBook freezes, its base (the underside towards the screen) is on the hot side. Most times I had an internet video (for instance YouTube) playing or some other Flash animation in Safari. I can reproduce the problem pretty consistently by opening one pretty intensive Flash site. www.group94.com is the site in question, and if you go Work at the top there (click cut the crap at the bottom after that) and open for instance the Experiences + Web Campaigns sections, there is some pretty intensive graphics action. After 10-20 minutes on this, the MacBook would freeze.

The freezes are like this: the screen is completely frozen (cursor not moving), but if there is an iTunes track playing it would continue playing. Also the Caps Lock and the Num Lock buttons work (i.e. they light-up their respective diodes). Command + Option + Esc does nothing.

My full MacBook Pro specifications are as follows

Model Name: MacBook Pro
Model Identifier: MacBookPro3,1
Processor Name: Intel Core 2 Duo
Processor Speed: 2.2 GHz
L2 Cache: 4 MB
Memory: 4 GB
Bus Speed: 800 MHz
Boot ROM Version: MBP31.0070.B05
SMC Version: 1.16f10

Mac OS X Leopard, 10.5.1 fully up-to-date

Please, if anyone has info on the problem or a possible solution... please let me know.

Does anybody have this issue resolved?

Hi all,

I'm having this same issue, thought it's taken me a while to find the Console.app.

I've done a 4 hour diagnostics loop with no reported errors, but load up a game like World of Warcraft wait for the problem to occur then check console output and there are literally hundreds of these types of messages

19/01/08 1:06:55 PM kernel NVChannel(GL): Graphics channel exception! status = 0xffff info32 = 0x6 = Fifo: Parse Error

I've spent the last hour on the phone to apple support and they have spoken to their senior ppl and basically desided that it's a hardware fault and i need to arrange an onsite repair.

I will post back here with the outcome when i have it.

Hi atomicbomb - I've been having the same problem (same Mac as you too I think - late 2006 24" iMac with the NVIDIA GeForce 7300 GT).

I can launch any app that uses OpenGL and watch the graphics channel exceptions start appearing in system.log. I use iStatPro to monitor the temp of the GPU, and it doesn't really increase; so I don't think it's heat.

I had this problem in Tiger, and hoped that it would be gone once I upgraded to Leopard. Of course, it's not, so it doesn't seem like it's a software issue (unless they're still using the old drivers?).

I'm really eager to hear what exactly they end up doing to get your Mac working. I was thinking about just getting a new graphics chip installed (~$300 - no AppleCare), but I'm reluctant since I'm not really sure that that will solve the problem. Please, please do let us all know what it takes to get it fixed. (Please, please let it just be the chip). 😉

BTW, it is possible to restart the graphics after a graphics channel timeout, but you need another computer (or anything that can run an SSH client). If you can SSH into your Mac with the crashed graphics and run:

sudo /usr/bin/killall -HUP WindowServer

...you'll restart the graphics and unfreeze your Mac. Unfortunately, that also immediately force-quits all of your apps and logs you out, so it may not seem any better than just a shutdown and restart. You might also want to try "kill"ing the app that's likely causing the timeout, but I never had much success with that.

Patrick