Is this a 4870 Glitch? Anyone else experience this? Flickering cursor?

[TheSpaz]

Okay, so I get a flickering cursor when I try to option-drag a file onto any sidebar item in the Finder.

Also, if you press cmd-shift-4, the cursor flickers too.

Is this a 4870 glitch or is it because I'm running it on a first gen Mac Pro?

 

[-SD-]

It's probably the 4870 as that seems to be the cause of several mouse related problems.