[anderkober]

in the older photoshop it will usually say your scratch disk is located in the same volume or partition as your system pagefile and could cause a problem. now it seems its no longer a problem having photoshop's scratch disk and windows pagefile on the same partition, but i think it is a good practice to have your scratch disk on another partition or entirely separate hard drive. i had my hard drive have a 30Gb partition just for my scratch disk. so far it suffice for me. hope this helps together with the previous posts above.