Display Problem in a MAC with Leopard OS

So my boss asked me today to check if I could find if his current problem was hardware based or software based.

I have Zero experience with Macs so I had to resort to google with no luck.

So far I haven't found anyone with a similar problem be either through a failed display or software caused via installing something or via hotkeys or whatever.

Whenever my boss opens applications like Quicktime or even just photos, the image appears distorted in matricial squares. The funny thing is that his desktop remains untouched while half of his icon bar appears distorted as well (this makes us believe its software based).

Whenever he uses applications like Firefox the problem doesn't present itself.

Any suggestions on what can I check?

I'm attaching both photos he took of his display.

A friend told me it could be the video-card, but I'd also like more input from you guys before telling my boss.

http://img.photobucket.com/albums/v2...l/DSCN0832.jpg
http://img.photobucket.com/albums/v2...l/DSCN0834.jpg

Should I have time before someonelse finds an answer I'll try to.

For the moment, it's not possible to decide wether it's hardware/software, because:
-If it's hardware, it can be a sub component, that derails only under some function calls.
-If it's software, it derails only under some function calls... too.

is the video car replacable in that mac and is there a mac with same video card around to swap?
What were the last soft installed? could it be related?

I'd search for CheckBoard image video problem in Google, not mentionning the mac at first, as it might be a common nvidia problem (I think macs are mostly nvidia)

Edit: After searching for 10 minutes, seems like a soldering/heat problem. Could be more of a hardware
problem. But Some threads in vista forums report same behavior, others when trying to connect TV out.
I don't know how proficient you are in computers, but installing a small livecd linux distro, a mediacenter one to be sure you get video, could be a way of knowing wether it's software or not.
I still do not know what kind of mac it is, but even with a livecd, I would disconnect any harddrive just to be sure there's no data corruption occuring.
I would also think of making a whole backup before anything else, because after all this might be a dying comp and your boss probably values data even more than the hardware.

Its a difficult case for me to describe since he only showed me photos as well... its one of those one-in-all equipments (hdd, monitor, etc in the same unit).

I've already suggested him to try connecting another monitor to check wheter its a problem of his display or something else. Though Im inclined to beleive its a video card failure.

A friend promised to give me a contact of a guy that repairs mac here in our town, so I think we'll be checking with him.

Still, thanks a lot for the suggestions David. I'll be sure to copy down the suggestion to tell the repairman.

I was seeing black here since I know nothing about mac, but my boss decided to ask me :p

This might take some time, but you should try to create a disk image of your boss's computer, back it up to an external drive, and reinstall the OS and see if the problem follows.