Thinkpad W530 here too and also dual boot. My win side is win 7 pro and is not allowed to update or connect to a network or internet. Runs like the day I installed it. Slower than Kubuntu. I had Mint KDE with the Plasma desktop but they ended it so I just swapped to Kubuntu. Less than 30 second startup and less than 5 second shut down. Had 8gb ram when I got it so I upgraded to 16gb.
That Thinkpad W530 is a solid piece of tech. Stil lruns well enough to get the job done, and more importantly, it’s easy to get under the hood for swap-outs and upgrades. I hate these new clamshell designs that require prying them apart with a special tool. Those things are designed by evil dwarves on crack.