Page 96 - GIGABYTE Service Manual-v3.0-110101
P. 96
5.4.2 Post 2B Repair
Example: AMD
MA78GPM-DS2H identified by:
01. Post code 2B.
02. OSC_14M_NB - the clock reference for RS780G.
03. R2503 bad and swap ok.
Signal Explanation:
OSC_14M_NB is REFCLK_P for RS780G is reference clock input for RS780’s
internal clock generator. There are two modes external and internal. External clock
mode: REF_CLKP is a single-ended, 14.31818MHz input from the external clock
generator. Input swing should be 1.1V. Connect REF_CLKN to VREF (0.55V) on the
motherboard. Internal clock mode*: 100MHz differential input.
Repairing Notes:
For repairing this issue, should focus on clock and NB.
Figure 5-24: Post 2B Repair
74
