I have not found a utility either but for the 2 Z87 boards I use with esxi 5.1 su1 (apply similar to all my dev esxi / hyper-v boxes from X58, B75, H77, Q77, H67, Z77 to Z87) - set in bios EIST C1 enabled / C6 report enabled others disabled / package Cstate to C0/1 - power management to balanced...