need new psu advice needed ty

[Bolton7935]

hey guys my pc been black screen a lot latly and i am sure its taking longer to turn on thinks its the psu tested ram gpu and cpu so its eaither the psu or board

so my question is what size psu i need i wont sli ever again had x2 480
using a ocz 1000 wat gold had it bout 3 years

spec is
x58 gigabyte ud3r
oc 5650 @4.3
12 gb ddr3
gtx 780 i usly overclock it but not now as it seem to black screen it more
1 256 ssd
2 hdd
also full custom loop with d5 pump

everone says get evga one want Fully Modular

many thanks

 

[Bolton7935]

Will 650watt be enough?

Thanks for the help

 

[Bolton7935]

Thanks for your help I'll get the 750w