I like Nikonbys answer if you're running Windows 4.x. The system resources are still a very crucial factor. They were the single most common reason Windows 3.11 used to lock up. System resources have very little to do with physical memory. Two programs, user.exe and gdi.exe set a stack in memory of a certain size. In Windows 3.11 that stack, if memory serves, 46K. Once either of those two stacks got filled it generated a GPF, or general protection fault, which means, I believe, that a program was trying to write to memory above the size of the stack. Since all 16 bit Windows programs ran in one address space that's verboten, the memory might contain program data and could be corrupted. According to Microsoft that problem was history because 32 bit programs run in their own memory space, plus the size of the stack was increased. I haven't been able to find out just how big that stack is, but Windows 4.x allocates memory very strangely. It allocates to itself the first TWO gigabytes of RAM and releases only a certain percent for program use. If more user memory is required it frees more memory by swapping part of the OS to disk. With the speed of your computer and the memory requirements of 3D stuff you may be generating GPF, but you aren't informed of this because they, according to MS, are a thing of the past. Forgive the lengthy explaination, but it explains why I support Nikotnby
Don Swayser