Q: 2009 imac white screen, safe mode ok'ish
I have a late 2009 27" iMac that has worked flawless since I got it from new, until recently. It started with it freezing with some randon vertical white lines, as in groupings of "III" spread out in random order over the screen. But only on the application open - being firefox at that time, not on the upper "command" line or launch pad below.
I then restarted it and it worked fine for like 5-10 min, then the same thing happened.
I then removed 2 8GB ram modules(I'll get back to those as they may have something to do with this) only leaving the original 2 2GB in place and tried again. Then it seemed to work fine for a full day, and I thought I was home safe. The 8Gb Ram modules had already been giving me headaches as I was able to start the machine with them once,but then could not shut it down and start it again unless I altered the number of RAM modules in the iMac by either putting the original 2 2Gb modules in with them or taking them out depending on the configuratin that was in the machine before shutting down. So this might have something to do with my problem. Apparently it only works with 4Gb ram modules and not 8Gb ram modules.
But back to the startup with the original 2 2Gb modules. This worked fine for a full day and then suddenly it freezed again. Then from this point on I haven't been able to start it in "normal" mode. I tried resetting NVPRAM(several times) resetting SMC, repairing disks from the disk utility and nothing worked.
What I can do though is start it in safe mode - which I am in now. This works OK - kind of slow and apart from the mouse pointer seemingly having some vertical lines attached to it, there is no graphical errors here.
I am leaning towards a failure of the graphics card, but then again why would I be able to see safe mode without "errors" (apart from the lines following the cursor)? I haven't installed anything leading just up to the problem that I can remember. I tried from safe mode to move what I could remeber being the "latest" installments to the bin(not emptying it, which perhaps I should to delete them properly?) and then trying to restart in normal mode, but without any luck.
Oh and first time I got it restarted in safe mode it gave me this(only pasting part of it - can do the whole thing if it helps someone):
*** Panic Report ***
panic(cpu 0 caller 0xffffff80173ce6fa): Kernel trap at 0xffffff8017310443, type 14=page fault, registers:
CR0: 0x0000000080010033, CR2: 0xffffff802d791900, CR3: 0x00000000b1e70000, CR4: 0x0000000000002660
RAX: 0xffffff802d791900, RBX: 0x0000000000000001, RCX: 0x0000000000000000, RDX: 0x0000000004000000
RSP: 0xffffff80b0be3be0, RBP: 0xffffff80b0be3c10, RSI: 0x000000004f463080, RDI: 0xffffff803021add8
R8: 0x000000000d001108, R9: 0x00000000e0000000, R10: 0x0000000100000000, R11: 0x0000000000000100
R12: 0xffffff803021adb0, R13: 0x0000000000000000, R14: 0x0000000000000001, R15: 0xffffff803021adb0
RFL: 0x0000000000010002, RIP: 0xffffff8017310443, CS: 0x0000000000000008, SS: 0x0000000000000010
Fault CR2: 0xffffff802d791900, Error code: 0x0000000000000000, Fault CPU: 0x0, PL: 1
If anyone has a good idea as to what I should try, then I would be more than happy. My thoughts are to either try to verify that the graphics card is bad - if possible without sending it off? Or try to "remove" all programs from the "startup list" of normal startup to see if it is a software problem. But anything is very welcome - I really hope I can get this baby back to normal, it has been so extremely stable for years.
iMac, OS X El Capitan (10.11.6)
Posted on Sep 28, 2016 2:36 AM