IBM Power AC922 8335-GTW Handbook page 26

Table 3. GPU problems and service actions for the 8335-GTC, 8335-GTG, 8335-GTH, 8335-GTW, or
8335-GTX (continued)
Problem
Fence errors in the operating system log
12 Power Systems: Problem analysis, system parts, and locations for the 8335-GTC, 8335-GTG, 8335-GTH,
8335-GTW, and 8335-GTX
Service action
1. Restart the system. Do fence errors continue to
be logged in the operating system log?
• Yes: Continue with the next step.
• No: This ends the procedure.
2. Does NPU chip 0 appear in the fence error log
entry?
• Yes: Continue with the next step.
• No: Go to step "4" on page 12.
3. Replace the following items, one at a time, until
the problem is resolved:
Note: Go to "8335-GTC, 8335-GTG, 8335-GTH,
8335-GTW, or 8335-GTX locations" on page
25 to identify the physical location and the
removal and replacement procedure.
a. CPU 0
b. GPU 2
c. GPU 1
d. GPU 0
e. System backplane
This ends the procedure.
4. Does NPU chip 1 appear in the fence error log
entry?
• Yes: Continue with the next step.
• No: Go to "Contacting IBM service and
support" on page 24. This ends the
procedure.
5. Replace the following items, one at a time, until
the problem is resolved:
Note: Go to "8335-GTC, 8335-GTG, 8335-GTH,
8335-GTW, or 8335-GTX locations" on page
25 to identify the physical location and the
removal and replacement procedure.
a. CPU 1
b. GPU 5
c. GPU 4
d. GPU 3
e. System backplane
This ends the procedure.