This specifically addresses your situation.
http://www.tomshardware.com/answers/id-1959070/pci-x16-watt-maxim um.html
I'm less concerned about the stated limit than what size slot it is ... according to the PCI-E spec, all **full height** x16 slots MUST be capable of handling 75 watts so as the post says, this may be more related to PSU size.
GT 730 DDR3, 64-bit = 23 watts
GT 730 GDDR5 = 25 watts
http://www.tomshardware.com/answers/id-1959070/pci-x16-watt-maxim um.html
I'm less concerned about the stated limit than what size slot it is ... according to the PCI-E spec, all **full height** x16 slots MUST be capable of handling 75 watts so as the post says, this may be more related to PSU size.
GT 730 DDR3, 64-bit = 23 watts
GT 730 GDDR5 = 25 watts
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