The world's oceans contain 1,335,000,000 km^3 of water. Heat capacity is 4.2 KJ / liter / C. So it requires 5.6e24 joules to heat the oceans by 1 C.
The world generates 20,000 TWh of electricity per year, and maybe 10% is for IT. That's 7.2e18 joules of electricity / year in IT.
So it would take 780,000 years to heat by 1 C. Or 780 years to heat by 0.001 C.
Other sources of global warming are far, far worse.