Blinking pixels on screen after Yosemite install

Check to see if you have Flip4 Mac plugin installed , if you do use the control panel to upgrade it to version 3.3.4.4, this corrected the problem for me.

Good luck

No, don't have Flip4 Mac. But: looks like clicking "reduce transparency" (in system preferences > accessibility) and then restarting may have resolved the issue*.

(*for me: seems like there might be multiple issues actually in play within this thread).

Kudos to Deltone, I'll give you props man. I'm so frustrated with this blinking pixel problem. You've helped immensely!!!

After going back and reading through this thread again, I finally decided to try turning off "Transparency" as the instructions left here indicated.

So far, no blinking pixels after 24 hours including a full day of work. I usually crush my machine, so it's a great sign that this problem is fixed.

Now I feel like a dummy. Thanks Pink Panther.

This is NOT related to Yosemite only. I am running Mavericks and have exact same problem in an year or so. Especially when i am running programs like Chrome, Adobe etc.

I do not have the possibility to adjust screen transparency in Mavericks. Someone users out there not running Yosemite who have solved the problem?

Pho2graph

I have a mid-2010 27" iMac 2.93GHz i7 16GB RAM Radeon 5750 1GB video RAM.

Started experiencing this problem with El Capitan. Can't recall if it started with 10.11.1 or 10.11.2... but it's identical as others have described. I've done all of the things others have tried: PRAM reset, SMC, installs, etc. to no avail. What's interesting is that it only happens when the hard drive is reading/writing. Otherwise the screen stays clear. I'm 99% sure this is the OS causing the problem as when I go to Windows 7 under Boot Camp, these symptoms NEVER appear. This definitely is not a hardware problem, but some sort of OS bug.

I have the same issue. Mid-2010 27" iMac 2.93GHz i7 8GB RAM Radeon 5750 1GB video RAM.

Turning off "Transparency", no blinking pixels appeared this morning after long time sleeping.

Thanks Pink Panther.

So Apple, assume it's a bug and fx it, please.

Pixels on my computer has been driving me nuts ever since Yosemite was upgraded...Ive had tech support come to help me through phone calls, tons of them...and i still have problems...my computer is shown as to what I have

OS X Yosemite version 10.10.5

2008, 24 inch

Processor 2.8 GHz Intel Core 2 Duo

Memory 4 GB 800 MHz DDR2 SDRAM

Graphics ATI Radeon HD 2600 Pro 256 MB

It works fine for awhile after I shut it down...BUT it always comes back, giving me frozen computer n pixels, please advise me what i can do to stop getting these problems...I'm not tech savvy...easy explanation or instructions would help greatly, thanks ya'all!

Has anyone got their problems solved similar to mine? Thanks so much!!

I had the same problem start happening last week. Resetting the PRAM and SMC seemed to help, but eventually the problem came back even after an upgrade to El Capitan. However, I just tired this and it worked instantly for me:

• Open System Preferences

• Displays

• Color tab

• Choose a different profile (e.g. Apple RGB)

• Choose original profile

Poof, problem gone (for now anyway.)

After months of searching - found your solution, and it worked!

Thanks, very much, Vegas!

Sorry - mistakenly gave credit to Vegas75 - thank YOU very much Pink Panther !