The Amiga Early Startup Control (ESC) screen, allows you to select Boot Options, Display Options, or Expansion Board Diagnostics.

How do I get to the ESC? 

Turn on or reboot your Amiga while holding down both mouse buttons. You can toggle between NTSC and PAL display modes by pressing any key on the keyboard.

How do I get OUT of the ESC?

To exit the Amiga Early Startup Control screen, select a boot option.

Select Boot for a normal system boot or Boot with No Startup-sequence to boot directly into an AmigaDOS Shell.

Selecting use implements your boot device choices for the current session only. When you reboot your Amiga, it returns to the same configuration as it had before you changed it. Selecting Cancel on the Boot Options screen cancels any changes you made and returns to the Amiga Early Startup Control Screen

Why would I want the option to disable devices?

The Amiga uses memory to support the operation of each of your hard disks, partitions or floppy disk drives. This extra memory used to maintain the added hard disks or an extra floppy drive can prevent some floppy-based games from running.

Select Boot Options from the Amiga Early Startup Control Screen and display the Boot Options screen. From this screen  you can selectively disable your hard disks, partitions and any external floppy drives. This will leave more RAM for your programs to run.

What is the information in the Boot Options Screen?

The boot options screen displays a list of hard disks, partitions and floppy drives in the Select Boot Device column. These devices are listed in the priority for the system to boot. You can select any of them to override this priority.

Control Active Devices is the status of these devices. Clicking on status toggles between Enabled and Disabled. If you want to disable hard drive devices in order to free memory for games, be sure to leave at least the floppy drive enabled.

• Note: If your system has more than one floppy drive and a program lets you use additional drives, you can leave each of those drives enabled in the Control Active Devices on the Boot Options screen.

Why would I want the option to disable caches?

You may want to Disable CPU Caches to retain compatibility with certain software that does not run properly when CPU caches are on. The 68020 (and higher) series processors have Data and Instruction caches that make them more efficient. If you don't have any compatibility problems you should not disable caches because caches significantly increase system performance. This option has no effect on systems with a 68000/68010 processors.

What about choosing display options?

Only available on Amigas with Enhanced Chip Set (ECS) or Advanced Graphic Architecture (AGA) chip sets.

Select Display Options from the Amiga Early Startup Control. This option lets you select the display type and chip set that your system uses.

Users with systems containing AGA chip sets can choose Best Available so that the system uses the AGA chip set. If a program needs OCS or ECS you must select either one for the system to "emulate". Systems containing ECS can "emulate" the OCS if selected.

How do I diagnose expansion board failures?

Select Expansion Board Diagnostics to display the diagnostic screen.  This screen shows a view of   information and the status of any expansion boards in your system.

It is recommended, if  you have an expansion board failure, to provide the manufacturer with any information from this screen, when you need help with a failed board.

Board Number - The number of the expansion board.
Manufacturer - The number for the maker of the board.
Product column - The manufacturer's product number board.
Status column - The status of the board: Working or Defective.

While booting the Amiga if an expansion boards fails, this screen is automatically displayed.