Can I get by with a 750 watt PSU?

Jay76

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Mar 9, 2011
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Working on a new build. My old 750 watt PSU seems to still be working fine. Will it be able to handle GPU's that require minimum 750 watts of power? When they say minimum of 750 watts does that mean specifically for the GPU, or for the whole system's supply of power?
The build is as follows
Asus Z87 A Motherboard
i7 4770K
WD Caviar Black 1tb HD
Samsung Evo 250gb SSD
8 gb Crucial Ballistics 1600 ram
Pioneer BRD
R9 280X or 290 gpu