Pc with xbox 360 power supply 205w

You'll need PSU connectors like these to get power to your PC parts.
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Socket 1155 motherboard needs 24pin main ATX connector like in the picture above.
Plus a 4 or 8 pin +12V CPU aux power connector.

HDD needs SATA power connector with 5V and 3.3V.
DVD needs SATA power connector with 5V and 3.3V.