Wow, big hard disk

If you're using Windows XP or probably Win2000, 224MB is definitely too low for Photoshop. Even with Win9X, you don't have much room for large files.

224MB is an odd number, sounds like 3x64+32 or 128+64+32. If all those chips aren't the same memory type and speed, it could cause trouble.

If you get additional RAM, make sure you only use matched chips.