Specifications

94 Product Errata
25759 Rev. 3.79 July 2009
Revision Guide for AMD Athlon™ 64 and AMD Opteron™ Processors
169 System May Hang Due to DMA or Stalled Probe Response
Description
Under a highly specific and detailed set of internal timing conditions, the Northbridge System
Request Queue (SRQ) may stall leading to a deadlock.
Potential Effect on System
Deadlock or machine check exception due to watchdog timer time-out leading to system hang.
Suggested Workaround
The BIOS should set NB_CFG Register[32] (MSR C001_001Fh) to 1b and set F0x68[22:21]
(DsNpReqLmt0) to 01b. No loss of performance results from this workaround.
The workaround for this erratum supersedes the workaround for erratum 131. When implementing
this workaround, the workaround for erratum 131 should not be applied.
Fix Planned
No