Q: What diagnostics are available?
For complete system diagnostics, there is the Rainbow's self-test and the 100B diagnostics. The self-test is very useful, but not very detailed. The 100B diagnostics are more thorough and descriptive. The 100B diagnostics are available at the Update archives.
For memory testing, you can rely on the self-test, which usually finds any errors, or you can use the PC100 Memory Utility. It is available at
(currently unavailable)
For graphics testing and picture alignment, you can use a program called the PC100 Graphics Option Daignostics. This tests the option's capabilities and allows for picture tube alignment. The program is available at
http://rainbow-100.com/archives/21/
For hard disk diagnostics, you can either rely on MS-DOS's chkdsk or you can use an early version of Norton Disk Test, which comes with the PC version of the Norton Utilities. To test the entire drive, including CP/M partitions, use WUTIL.