Extremely Slow Performance W/O Diag Failure

This document outlines Field Change Order (FCO) PMAG-FB-F001 for Turbochannel systems equipped with a PMAG-FB (High 3D) graphics option built prior to May 1991. The issue involves the High 3D module incorrectly responding to DMA error signals from other system components, causing the system to hang or run extremely slowly. The solution is to upgrade affected boards to the current revision to properly isolate DMA errors. The FCO is to be implemented on an "as needed" basis. The document includes serial number identification for affected units, a step-by-step installation procedure, and LARS reporting codes for field engineers.