Just to add to the above ,the Pentiums FPU is about 20-25% better than the K6-2 (unless 3Dnow is being used) ,so I guess it comes down to what a server needs more ,FPU performance or Integer? (don't ask me I don't know!😱😉).
I also agree that a K6-2 will use less power than a Pentium ,but does that really matter? ,it's only going to make a small difference to total power useage.
BTW are you sure that the m/brd supports the lower cpu voltages for the K6-2?