Page 82 - GIGABYTE Service Manual-v3.0-110101

5.2.5 GTLREF1 Fail

Example: Intel
G31M-ES2L identified by:

01. Post code C1.
02. GTLREF1 is only 0.7V (should be 0.9V)
03. VTT_OR and R1, R3 ok.
04. C1 swaps ok.

Signal Explanation:
GTLREF is a reference voltage for CPU to compare
And determined high and low levels of the input buffers.

GTLREF fails so Front Side Bus Cannot work correctly and post code C1.
GTLREF is also important for CPU detection.
Signal Core 775 CPU – GTLREF
CORE2 Duo – GTLREF0~1
Quad-CORE – GTLREF0~3

Figure 5-9: GTLREF1 Fail Check

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