Apple Mac OS X's video memory usage
Anand Lal Shimpi:
While it would take 70 normal windows to max out the 512MB of video memory on a GeForce GT 120 at 2560 x 1600, it would take less than nine 12MP images open in Photoshop to do the same. And once again, you don’t get that memory back when you close your images - only after you exit Photoshop. Most other windows in OS X will give you your GPU memory back as soon as you close the window.
The post is a snippet of his full review of EVGA’s GeForce GTX 285 Mac Edition video card. He's published it ahead of his full review to gather feedback on this new approach. I prefer the whole article instead of little snippets.