2 S1's and a S3 PSU question..

[irxbtc]

Quick question here

I have a evga 750w Gold rated modular psu that I'm currently running my s3 on. I just picked up 2 s1's and a 1200w server psu (3 PCI-e cables for a total of 6 connectors) for $50 off a buddy. I'm planning on running at stock speeds so no overclocking.

What would be the best way to run this setup?  I was thinking of running all three off the 1200w but I'm a little hesitate unless I would get some sort of feedback that it wouldn't burn anything up. I was also thinking about running the two s1's off the 1200w and the s3 off the 750w. I do plan on buying another s3 but really don't want to buy another PSU. Future planning in consideration.

Thanks!