Solution:

Due to mechanical limitation, the PCA-6275 doesn't be installed into AWS-843. User can choose PCA-6276L to replace PCA-6275. In addition, the following CPU boards are suitable for AWS-843. PCA-6159 series PCA-6155V PCA-6166 series PCA-6168 series PCA-6176 series PCA-6276 series PCA-6359 series (Updated on 4/10/2000)