Well, you have to define 'successful'.
All of the silicon acquisitions, particularly in the 1999-2001 range, died either a mercifully quick or painfully slow death as Intel tried to assimilate both the silicon and the teams they acquired. None of that stuff, even in derivative form, is around today.
Altera is still WIP. They were largely left alone to continue their cash flow, and their decline seems abated, for now. I do not hold out much hope for integration with Xeon, but if they can transition this year to newer processes, they'll be OK as an FPGA division. For now.
Infineon - probably positive, if it led to an Apple win, even for a short time.
McAfee is debatable. They were also never integrated into Intel, socially, organizationally or technically. Their own culture survived, and they are out, with little hit to their bottom or top line numbers (no growth, but no loss). Intel will still reap benefits from their position in the spin-off. I'd call it a push.
WindRiver was a disaster. Also never really integrated, and it's a mess. Some good people there.
Other SW acquisitions are hard to tell. Cloudera is off to a bad start as an investment - others here are suggesting Intel just buy them outright to hedge their initial investment. Whamcloud, Mashery, Aepona, so many others - these just make me cringe.