dual monitors going black!
Hi all,
I have a Mac Pro with an upgraded ATI Radeon HD 5870 graphics card installed (about 2 years ago). I've had no issues at all until recently. About a month ago, I decided to go dual monitor. I have an attached LED Cinema Display (27") via mini displayport, and an older Studio display connected via DVI. I had no trouble at all until 2 days ago. I went to use my computer, and could not get the displays to come on (with a tap of the keyboard). The computer was not asleep. So I did a hard restart (ie, held the power button in until it turned off, then turned it on again), and the monitors came on again. But about 15 minutes into my using the computer, they went black again. I tried unplugging them from the back of the computer and plugging them in again- no luck. So another hard restart, worked ok for about 10-15 minutes, then black. I finally disconnected one of the monitors, and everything seems to be ok for 2 days now. I've tried placing a mini displayport adapter onto the DVI plug, thus giving me two mini displayport monitors- no luck.
There aren't any other issues that I'm aware of (ie, the computer seems to be working fine otherwise). Could this be a video card thing? Any suggestions?
Thanks.
John
Mac Pro 2 x 2.66GHz, Mac OS X (10.7)