Operating System and Applications Before beginning any hardware design the user’s applications and OS must be evaluated for their requirements. If UNIX or some variant of Linux is to be used the hardware manufacturers must have drivers to accommodate that variant and version. With Microsoft Windows this is not a difficult task although if the software is extremely old it may cause hardware issues. Additionally, high end applications often use features included in specific hardware to speed their processing. These should be evaluated by a cost benefit analysis. It should also be noted that due to addressing limitations, 32 bit OS’s are limited to the use of 3.2 GB of memory regardless of the amount of memory installed in the system. On the other hand a 64 bit OS can address over 4 TB of memory and since most motherboard are designed for 128 GB of memory or less it can easily manage all available memory.