In this page, I'll show you a tips.
Press and hold the F1 key then power-on the computer, you can run diagnostics or can access setup screen. There are hidden functions in setup screen.
The left picture is normal test screen.
When you press [Ctrl]+[A], you can access to advanced diagnostics.
When you press [Ctrl]+[K], you can test keys. To quit test screen, you press [Esc].
Officially the max memory size is 24MB. But if 32MB memory card is installed, you can use memory 40MB totally.