5

22564B-1—February 2000

AMD-751™ System Controller Revision Guide

Preliminary Information

3

PCI ARB_DIS Bit Set When DMA is Active

Products Affected. C3 and C5

Description. If DMA is active when ARB_DIS is set, the system can hang.

Potential Effect on System. System hang could occur.

Suggested Workaround. Prior to setting ARB_DIS, software suspends all DMA activity.

Resolution Status. Fixed in a future revision of the AMD-751 system controller

.

8

GART Requestors Do Not Work With TLB Caches Off

Products Affected. C3 and C5

Description. Only partial support exists for the mode where GART TLB caches are disabled. GART

caches disabled was intended primarily for performance evaluation, and is not supported.

Potential Effect on System. None

Suggested Workaround. The BIOS should set BAR1: Offset 02h bit 2.

Resolution Status. None required, proper operation