White noise-like bands appearing on photos

[Evagertie]

Ive been working on a postcard project in Photoshop, and suddenly if I copy a photo into a new layer, or open a file in photoshop, it has a band at the top and mid photo that looks like bands of black and white tv noise.  What have I done?  Thanks!

[Omar.Fathy]

What about your VGA Cards ?!
If everything is ok in photoshop, The problem will be in the VGA/GPU Card.

[Evagertie]

Thanks, I'm not sure what that is.  I googled it, and it looks like a computer part. My iMac is only 2 months old.  The problem just occurred mid project today.  I just added the free trial of indesign today, but photoshop was working fine for a few hours after that. 

I keep getting a message about converting from 32 bit colorspace.  Could it have something to do with that?  Sorry I haven't used these programs in about 9 years, so I'm not so great with this stuff.