imac crashes with gpu reset since ElCap

Just an update on this issue, Yosemite was crashing as well, so took my iMac to the apple gods, they offer two options:

- for 400 quid replace my video card, LOL

- or recycle my mac and get a voucher for 50 quid ROFL

I installed ubuntu on it which hasn't crashed for 6 months now... at least I have a working machine

Reset the SMC 2-3 times Resetting the System Management Controller (SMC) on your Mac - Apple Support unplug from the back of the iMac not the wall.

Try a Safe Boot Try safe mode if your Mac doesn't finish starting up - Apple Support

iMac (27-inch): AMD Radeon 6970M Video Card Replacement Program - Apple Support

I have a mid-2011 27" iMac and am experiencing similar problems. Mine was fine for a while on ElCap but in the last 3 weeks I've had many blue screens where everything freezes and quite a few instances where the computer restarts.

I had it in to a local Apple store and the said they couldn't replicated the problem. However, if it persists, they said they would replace the video card under that replacement program that was referenced in an earlier post, even though the machine is out of warranty.

Just starting to do some troubleshooting on my own. I had a crash report for a WacomTabletDriver. I hadn't used a tablet on this machine for a couple of years, so I deleted anything to do with Wacom. Don't know if that was part of the problem because I'm still getting gpu restarts. But so far no blue screens.

Hi,

just to report back on this.

After the latest .4 patch release for ElCap i was still getting lots of graphics crashes so decided to downgrade.

I have formated my drive, reinstalled Lion and upgrade to Yosemite.

So far so good. I haven't had a crash in the last week and it was running constantly. With ElCap i hardly managed to get 1 hours usage.

So at this point it's probably hard to says that Elcap has a serious bug affecting 2011 iMacs with AMD Radeon 6970M cards.

Looks like I'm stuck with Yosemite, I guess Apple cannot be bothered to support old hardware.... same on you apple ... ( I have reported the bug to apple support and they never even bother to reply )

Same issue with late 2015 iMac 27 inch retina with AMD Radeon R9 M395X 4096 MB. iMac is 4 days old, tons of these GPU resets and mostly these lead to full kernel panics and reboots. For anyone else having this, all of the following have failed to make a difference:

SMC reset,

NVRAM reset,

Safe boot,

Disc check with Disk Utility

Apple diagnostics show no hardware issue,

Tech tool PRO 8 shows no problems in RAM or any other system including VRAM, (OWC 32 GB added to stock 8GB)

Happens with no peripherals attached other than keyboard

Reinstall OS X 10.11.5 from Recovery partition still happens

Updated all the Apple and 3rd party software - Microsoft, Adobe, Earth desk, Drop box, ClamVX, Stuffit deluxe, Flip4 mac etc etc

Still has the annoying crashes. Going to Apple Genius desk to see about replacement.

Have yet to try the remove RAM trial, but seems unlikely to make a difference as the errors are almost always GPU resets which I believe is a completely separate chip

Before you go to the genius bar you should at least remove the third party ram and test. If the panics persist remove the original ram and test.

Thank you Mike. I finally tried that and the result was odd. I removed the original Apple RAM, left the OWC RAM in place. This solved the problem too my surprise. Did the reverse and problem came back, which is not what I expected.

It may have been the actual slot where's the RAM were seated rather than the modules themselves, but I was too pleased to spend more time troubleshooting. I took it the iMac to Apple, expecting a RAM replacement, instead they chose to replace the whole MAC.

What is also odd, is that neither Apple Diagnostics or Tech Tools Pros RAM testing reported any problem with any RAM several times over the week. I also had switched the locations of the RAM in my testing at least once.