Screenshots are distorted on Mac Mini with NVIDIA GeForce 9400M

Solution 1:

Well, Macs and NVIDIA. It seems that either you just have a minor software glitch, or your graphics card is faulty. In any case, consider running all software updates possible — from your previous question history, I think you'll get Snow Leopard soon?

NVIDIA had problems with their 8600M GT chip before, when Apple had to replace the logic boards of a large number of MacBook Pros. This is still covered under warranty, even four years after buying.

As for your particular graphics card model, there are quite a few people that deal with similar problems and distortions on the NVIDIA GeForce 9400M:

• Graphics glitches occurring with the GeForce 9400M?
• Nvidia GeForce 9400M makes my MacBook Pro screen blinks

In such a case, the only resolution would be to have the logic board replaced, which is a quite expensive procedure for any Mac, unless it's still covered under normal warranty or AppleCare protection.

You can be lucky that it only affects screen shots. As you're probably not playing any 3D games, you haven't seen any other issues so far. You might try using an alternative screen shot program (like Skitch, Jing, InstantShot), and see if that gives you better results, but I can't really promise that'll work.