On 14 January 2014, 15:26:41 UTC, PrimeGrid’s 321 Prime Search project found the mega prime:
The prime is 3,259,959 digits long and enters Chris Caldwell's The Largest Known Primes Database ranked 12th overall. This is the largest known 321 mega prime and the largest prime found to date at PrimeGrid!
The discovery was made by Sai Yik Tang (tomakey) of Malaysia using an Intel(R) Core(TM) i5-2400 CPU @ 3.10GHz with 4 GB RAM running Microsoft Windows 7 Enterprise. This computer took about 17 hours and 40 minutes to complete the primality test using LLR.
The prime was verified on 14 January 2014 20:23:24 UTC, by schnabelt of Germany using an Intel(R) Pentium(R) CPU G850 @ 2.90GHz with 4 GB RAM running Microsoft Windows 7 Enterprise. This computer took about 22 hours and 47 minutes to complete the primality test using LLR.
For more details, please see the official announcement.