you sure the error was something like they preview couldn't be saved? that can be a common error in Illustrator, the file saves out but not the preview.
also, how much disk space do you have available? can you move one of your photoshop scratch partitions to another drive?
I could be wrong, but the only time you will get a "not enough memory" error in PS is when you filled up all your scratch disks. Photoshop has it's own built in "Virtual Memory"