The problem appears to be related to the use of multiple NVIDIA cards. As far as one can tell, using a SINGLE NVIDIA card or a combination of one NVIDIA card and one ATI card eliminates the problem.
Using a single GT120 card works, but 1) depending on your type of monitor/screen size, you'll need an expensive DVI-to-MiniDisplayPort adapter to use the second port and 2) there will be a noticeable drop in video performance, primarily because now each monitor only has 256 MB of VRAM. Not dramatic, but noticeable.
I personally went with keeping one GT120 for my secondary 30" monitor (512 MB of VRAM) and using a 5770 for my main 30" monitor (1 GB of VRAM). There is a small boost in video performance on the main screen, and no more KPs.
The installation is fairly straightforward, and the ATI card, while significantly bulkier than the GT120, does not appear to be making more fan noise.
This GT/ATI approach has worked for me for a month too without a KP. Curious of 10.8.4 release will fix it all too. I noticed an NVIDIA CUDA update that launched right after I did the OS update. Might be because I had installed updated NVIDIA drivers during the search for a solution before...although they didn't work. Only taking out one GT and replaceing with 5770 did the trick. And I run 4 monitors, 2 25s, 26 and 27 (I think). Although I don't do major video work, etc. Just a lot of programs, docs, browsers etc. for running a small marketing company.
So the "rule" is not just more than one GT120 which took a while to confirm and substantiate, but to expand that to "more than one Nvidia card" actually makes more sense and logical.
And annoying. That means two GTX 670s might break the system, too. A glaring defect.
Some people still have trouble swallowing and accepting the GT120 "theory" except that everyone that changed to ATI + Nvidia or just one card if possible, the problem would always go away.
I went with purchasing a single Sapphire 7950 for Mac, and its been 3 weeks and no KP! I pulled all the nvidia GPU; since I freed up my PCIe, I got a USB3.0 controller too.
The Mac 2009, should handle two 5770 (they each use 1 PCIe supplemental power; and the the Mac has 2 available), the GT120 does not need supplemental power.
Hi, for those who are interested, since I unistalled flash and use chrome which has a native flash application inside, I don't have any KP for more than 3 weeks.
Only Skype is causing troubles, so if you don't need flash and use facetime instead of skype, maybe it's a half solution but for now it's working and i can have time to think about buying an expensive new video card.
I know i've been upset agaisnt mac on my last posts, but to answer to some people who were a bit nervous against me, i want to say that it's not because i own a mac pro that my bank account is unlimited, the radeon card is probably nice, but sometimes you just can't afford to buy one just to avoid KP.
Well it happened... latest drivers, uninstalled Flash, not using Firefox and I got a Kernel Panic last night, then another this morning!
All I can do now is remove the GT120 card and use two monitors off the 8800 card for now and then see if OS X Mavericks will sort the problem? Guess I'm lucky in that my ageing Early 2008 Mac Pro is going to be supported by Mavericks, although whether or not it fixes the multiple video card issue remains to be seen.
No More Panics!
This is my first post to this thread, and thanks to all for guiding me to a solution
I am all but certain that the display-related kernel panics are due to the presence of two nVidia graphics cards, not necessarily two GT 120's.
I came by my certainty when I replaced one of my GT 120's with an nVidia GTX 650 Ti—and the kernel panics continued—then replaced the nVidia 650 with a Radeon 7700—and the kernel panics stopped. That is, I have 80 hours of use on the Radeon card (paired with one of my GT 120's) and have experienced no panics. With two nVidia cards, there would have been 12 to 24 panics over the same period.
(It is possible that the problem may be caused by a combination of a GT 120 and any other nVidia graphics card, not necessarily another GT 120, but I just didn't want to invest any more time troubleshooting.)
It irked me to lay down my money to "fix" a problem of Apple's creation, but given how much these display-related kernal panics have cost me in productivity, I wish I had set my principals aside a few months ago.
Hope this is helpful.
About the new graphics card:
It's an ASUS HD7770-2GD5, and I'm very happy with it. It's ever so slightly noisier than the GT 120 it replaced, is much faster, and cost only $120 (after a $15 rebate). My system sleeps properly, wakes faster than it used to, and can play full-screen, streaming HD video on the secondary display without video stuttering.
The only downside I've discovered so far, and it's a small one, is that System Report can no longer gather info on the PCI slots, but I understand that this would be the case with any other non-EFI graphics card installed.
The ASUS is in PCI slot 1 and a GT 120 in slot 3. I separated the cards to allow for better ventilation, and "yes", the GT 120 runs just fine in a 4-lane slot. The ASUS drives the main and secondary monitor, the GT 120 the tertiary.
Some observations and suspicions concerning the nVidia graphics card-related kernel panics:
ALL of the panics my system experienced had the following in common:
- In the panic's System Diagnostic Report, two kext's were always back-traced, "com.apple.NVDAResman" and "com.apple.GeForce".
- Safari and/or Firefox were open, but not necessarily the active application.
MOST of the panics had these in common:
- A browser window was open in the secondary or tertiary display. (Panics were less likely to occur if only one browser window was open and it was on the main display.)
- One of the browser windows was being scrolled.
- The panics started when I installed 10.8.2. (I didn't upgrade to Mountain Lion until 10.8.2 was released.)
- The panics increased with OS 10.8.4.
- Every two weeks or so, my Mac Pro would refuse to recognize the tertiary monitor when waking from sleep. The display would not appear in Display Preferences. Sleeping & re-waking the system might solve the problem, but a restart was usually required.
My gut tells me that the WebKit is involved, but I'm so completely "done" dealing with this long-standing issue, that I'm going to leave it to some more patient soul to investigate.
<Anyone tried with the latest webdrivers for geforce cards?
I will be testing this during the week, to see if it resolves the issue, I've got a lot of mxed 2009 and 2010 mac pros most of them with dual 120 cards, hopefully this works so I can continue deploying 10.8.4 throughout the organization.
I use Chrome mostly, and I get the KP only about every 1-2 weeks (Early 2009 Mac Pro, Dual 120s, 3 monitors). I occasionally have to use Safari or Firefox to check my sites work in them.
I suspect that it's some kind of timing bug, so happens randomly but is more likely under certain situations that stress the system, meaning using certain bits of software. Something like the OS is not properly marking video memory as used in a thread safe manner, so two processes get a hold of it, then one releases it, then when the second one tries to, it's gone, so it crashes.
The most likely thing would seem to be video codecs. In particular I noticed a KP happened immediately upon playing a DivX video. I would also expect some games to have the problem, but I don't use the Mac for games that much.
I uninstalled Perian (multiple video codecs), that might have helped. Maybe removing other quicktime components might also help.
Having previously replaced the kernel panic inducing dual GT120 graphics cards, I recently re-introduced a single GT120 to my Mac Pro without problems.
My Mac Pro has been stable with a single GT120 and ATI 5770 for a month now.