Hard to say it is a power problem since most are shared between the two except actual power off/on.
Could be a heat problem (chip level), try removing panel sides and blow fan from outside through the case and see if it helps. If yes then it is a heat related issue.
Since things are shared it is difficult to fault the P/S unless it is just on the edge. Disconnect power from unneeded device(s) and see if that helps. If yes then perhaps a power supply.
Post more information about computer type, especially motherboard and perhaps more specific answers will follow.
When I first turn on the computer, the fan comes on and the hard drive starts but no beep. Only if I push the reset button then it starts up normally. Any suggestions?

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