Phanteks power splitter

[Steve-Isaaru]

So I have two gaming rigs one i5 with a gtx 760 and an i7 with a 1050( both are receiving minor gpu upgrades). 

One is mine and another is my girlfreinds, both are in separate but identical core p5 cases. Id love to mod the two cases to be one back to back rig. 

 

My problem is I feel both my PSUs are a bit over powered and I hate running them both all day, ones a seasonic platinum80plus 660 watt and the other is the same thing only 780 watt. 

 

Has anyone used  

https://m.newegg.com/products/N82E16812987009?nm_mc=KNC-GoogleAdwords-Mobile&cm_mmc=KNC-GoogleAdwords-Mobile-_-pla-_-Cables+-+Power+Splitter+Cords-_-N82E16812987009&gclid=Cj0KEQjwt6fHBRDtm9O8xPPHq4gBEiQAdxotvPqTvOnEUyQixCdEDAnTI54E6K4yKaxalw45Vm1AfhAaAsDu8P8HAQ&gclsrc=aw.ds

 

To run two systems off one rig? Or would a simple Y splitter cable be okay? Is one safer than the other? Or is their  a psu designed for this very thing? 

 

Id rather not buy another psu but where both my machines are k series and their overclocked I dont wanna hurt the systems.

 

So what psu/ accessory would best accomplish this 2 systems "one case" project.