I've been using CS3. Without un-installing CS3, I installed CS6 . . . actually both 64bit & 32bit. I had several problems when running. For example, images often were not completely visible after loading . . . part of the image showed as transparent. I could duplicate the layer & all was ok, with both the new & original layers. This hasn't been a major problem, but is a nuisance & indicates that something is not right. Several features even cause "Photoshop CS6 has stopped working". Thankfully, I could always fall back to CS3 when a problem cropped up, altho' it was a pain having to save so often.
I deactivated CS6 and uninstalled (via Control Panel). I then re-installed, installed updates & re-activated . . . same problem when images load. I just re-installed, so I haven't had a chance to test other things.
I've postponed installing Lightroom4, hoping to solve CS6 problems first.
Update your video card driver from the GPU maker's website.
You've got an older version of the driver that has serious bugs in it.
I downloaded & installed Nvidia GeForce G210 driver. Started CS6 . . . opened several JPG images . . . each was completely visible after loading. That sometimes happened before, so I'm not completely sure it's fixed . . . time will tell.
Now I have another (different problem) . . . The Type tool will not work. I get "Could not complete your request because something prevented the text engine from being initialized."
For what it's worth . . . each time I clicked to make the above Bold & italics I got a Windows Internet Explorer message "Are you sure you want to leave this page?"
EDIT . . . I rebooted (again) & everything seems to be working . . . EXCEPT the Windows Internet Explorer message "Are you sure you want to leave this page?"