Mac Pro 2010 with two installed HD For the last several months the screen has started to progressively pixellate eventually causing a hang . I tried to do a hardware check but it didn't start. Today wont boot up at all chimes , then c

- Try resetting the SMC and NVRAM/PRAM

Intel-based Macs: Resetting the System Management Controller (SMC)

About NVRAM and PRAM

- Try starting in Safe Mode

OS X: What is Safe Boot, Safe Mode?

- Boot to Recovery and repair the startup disk

OS X: About OS X Recovery - Apple Support

Open the side cover and observe if the fans are freely spinning included the one on the graphics card. Blow dust from fans and other places.

What graphics card is installed? The card could be failing.

To open the drive:

hold down the Option key at startup. This invokes the Startup Manager, which draws a gray screen and scans every possible Hardware address looking for potentially-bootable drives. Over several minutes, it will scan them all and be done, and the watch cursor will go away. At this point the Eject button on the keyboard becomes available, and if you insert a DVD and close the drawer, it will scan that drive for boot-ablity and list an Icon for it, if appropriate. You can choose that icon and tell it to proceed.

kauribob wrote:

Mac pro 2010 2 HD Mac OS 10.10.5

Start up disk

has been pixellating and then the screen hangs

Today wouldn't start after powering down and quitting to get rid of the pixellations . Now powering up only leads to a series of chimes and no progress.

What can I do ?

the pixellating means the video/graphics card was beginning to fail and should have been taken care of then.

Search on line for apple parts -- there is a place in california that does deal in them -- your card may just need to be refurbished - as in re-solder all of the connections so it works again.

kauribob wrote:

Thanks all will look at the video card

Just an FYI -- my card failed fast after I dusted it - and worse after second try of dusting -- I could not do the hardware test either - guess it has something to do with the memory on the card -- I determined the card was bad because the monitor was fine when attached to my old mac.