The new ROM firmware was expanded to 256 KB and contained the System 5.x toolsets. The newer toolsets increased the performance of the machine by up to 10%, due to the fact that less had to be loaded from disk, tool ROM read access being faster than RAM, and their highly optimized routines compared to the older toolsets (pre-GS/OS-based). In addition to several bug fixes, also added were more programmer assistance commands and features, a cleaned-up control panel with improved mouse control and RAM Disk functionality, more flexible Appletalk support and slot-mapping.