Today I picked up a few machines including what I thought was an #IBM #PentiumPro 200.

It turned out to be a DUAL Pentium Pro 200. Sweet!

#VintageComputing / #RetroComputing

Trying to decide which OS would be best for this setup.
Ooh! It's #Y2k OK!

@Cloudscout

This only confirmed my instinctive answer to your operating system question.

Windows 2000 Professional if youโ€™re going with Windows.

@Cloudscout I ran Linux and NT4 on my dual P90, so those would be my suggestions.
@breadbin @Cloudscout I agree, NT 3.51 or 4 for Windows, Linux 2.0ish for Linux, or maybe BeOS.
@breadbin @Cloudscout Maybe AIX if it's a supported configuration.
@elb @breadbin ooh. I didn't think of trying BeOS on this. The funny thing is that I specifically planned to run BeOS on two of the other systems I picked up at the same place tonight (a Mac and a Mac clone).

@Cloudscout Depends on what you want to do with it, really.

My choices would be either "IBM Warp Server Version 4 Advanced SMP" or Solaris.