This is my recently reconfigured rack of 5830s. When I'm done with the others, I'll post them as well.
https://lh5.googleusercontent.com/-FK9VQ3OkDXo/T7SBSNrX82I/AAAAAAAACCw/E6raKULPFn8/s751/IMAG0052.jpg
I spy with my little eye... a Lenovo 60 watt AC adapter. https://lh5.googleusercontent.com/-FK9VQ3OkDXo/T7SBSNrX82I/AAAAAAAACCw/E6raKULPFn8/s751/IMAG0052.jpg
It looks to me like it's an "old" 16.6V (or whatever it was) with the yellow plug. So it might still be IBM, not lenovo
Its the 'new' Lenovo yellow plug.