Why does my Mac Pro displays static and garbled junk on both displays?
January 13, 2010 12:56 PM Subscribe
Please help me correctly diagnose this video/display problem on my 3-year-old, out-of-warranty Mac Pro.
My Mac Pro is out of commission. It's from November 2006 and the specs are: 2.66 ghz quad xeon, 2gb ddr2, nvidia geforce 7300gt 256mb, 1x500gb hdd, 1x1tb hdd, OS X 10.5.8. The chain of events is as follows:
- In general, this computer is on 24/7.
- For a few months, my Mac Pro tower would emit a single beep at seemingly random times. Never at boot time, but after the computer had been on for hours, days, or weeks. I foolishly ignored this because I could only find information about successive beeps at boot time signifying memory failure.
- A few times over the past year, the system was unable to locate the startup volume. I'd reboot and everything would be fine.
- Recently, for a day or two the computer would freeze up - one of the drives would spin up if I tried to open a file or launch an application. The spinning beach ball of death would appear and I would have to reboot.
- Shortly after the system began locking up, strange artifacts would appear on the display. Weird lines, small spots resembling static or garbled lines and colors.
- After a day, I could not even boot into anything usable as I would just see scrambled lines (like this) or solid blue screens with the spinning beach ball (like this).
- At present, I can boot up and get to the login screen. A few small bits of static appear here and there. When I click on my user icon, I see the static.
I tried the following things without success:
- I have a bootable backup on an external disk. Using Option+boot I selected this as the boot device and replicated the problem.
- I tried to Option+boot and choose the OS X install disc, however my optical drive does not appear as a bootable option.
- I tried to Shift+boot into safe mode, but the system ignores the key press and goes straight into a normal bootup.
- Cleaned out the case with a can of compressed air.
- Removed the graphics card and re-seated it in a different PCI slot, then tried to boot up.
I don't think I'm dealing with a bad hard drive because:
- I can mount and read my boot-able external backup via usb on my MacBook Pro.
- Using the MBP, I can mount and read both of the Mac Pro's internal volumes over my home network.
This leads me to believe that this is a video problem. I find it unlikely that both of my cinema displays failed at the exact same time. Maybe this is a logic board error (I hope not), or just a bad video card? Or could I have some corrupt system files/video drivers.