50 Cent Sells Connecticut Mansion For $3 Million, Donating Money to Charity

50 Cent just made a massive donation to charity ... and the funds are all thanks to the unloading of his mega-mansion in Connecticut.

50 just sold his 50,000 square foot pad -- with a whopping 21 bedrooms and 25 bathrooms -- for $3 million. A source close to the rapper tells us every penny from the sale will be donated to 50's G-Unity Foundation ... a project that provides grants to non-profit organizations that focus on improving the quality of life for low-income and underserved communities across the country.

50's been trying to sell the massive property for years ... he bought it way back in 2007 for $18.5 million.

The baller pad is palatial ... with 9 kitchens, outdoor infinity pool and grotto, indoor pool, helicopter pad, casino, nightclub, basketball courts and a pond!!!