| RS/6000 Microcode Updates | ||
| Severity Definitions |
| Classification Flag | Symbol Meaning | Description |
| HIPER | High Impact/PERvasive | Should be installed as soon as possible. |
| SPE | SPEcial Attention | Should be installed at earliest convenience. Fixes for low potential high impact problems |
| ATT | ATTention | Should be installed at earliest convenience. Fixes for low potential low to medium impact problems. |
| PE | Programming Error | Can install when convenient. Fixes minor problems. |