Also usually less heat and ability to increase density of multi chip designs.
Intel had the problem that the Ivy Bridge CPUs ran hot faster than Sandy Bridge since their surface to dissipate heat was reduced, making the Sandy Bridge the better overclockers choice - it has it's disadvantages too to go too small

I think Ivy runs hotter because Intel didn't soldered the chip and thermal plate. Since the Ivy chip itself doesn't run as hot as sandy, Intel could save money in production by putting simple conductive paste between these components.