In January 2008, at the 6th Gibtelecom Chess Festival in Gibraltar, Bu came joint first scoring 8/10 (+7−1=2; Elo performance 2834) but lost on the two game blitz play-off tie-break to Hikaru Nakamura. In April 2008, Bu competed at the Russian Team Championships in Dagomys, Sochi for the team "Shatar-Metropole" (Buryatia), where he achieved a score of 6½/10 (+3−0=7) and a performance rating of 2771. In his super-tournament debut in Sofia, Bulgaria at the M-Tel Masters (category 20) tournament on May 7–18, 2008, he came fifth out of six players (Levon Aronian, Ivan Cheparinov, Vassily Ivanchuk, Teimour Radjabov, Veselin Topalov) having scored 3/10 (+1−5=4; Elo performance 2594).