eXtreme Power Supply Calculator Lite v2.5
check out this PSU calculator. and its slightly overestimated compared to real world usage
also check out this chart
check out the computer system! core 2 duo and 2gb DDR2 RAM
the video card im getting is the HD 2600Pro which has half the processing power of the HD 2600XT
so as people can see its quite safe for 300PSU unless your doing dual SLI and stuff
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