PDF schematic for the MSI H61M-P21 (B3) motherboard, MS-7680 revision 3.2. H61 refers to the Intel chipset and B3 to the chipset stepping revision noted in the model name. The drawing is useful for diagnosing no-power faults, tracing the standby rail and power-good chain, testing VRM MOSFETs and finding where the BIOS chip is wired. MS-7680 was made in several revisions, so check that 3.2 is printed on your board before relying on component placement or values. Any PDF reader works.
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