In 1998 he won the World Junior Championship and as a result he was granted the title of Grandmaster (GM).
[1] In this event he lost in the first round to Peng Xiaomin by ½-1½, thus exiting the tournament.
The next month he won the Politiken Cup in Copenhagen on tiebreak score over Leif Johannessen and Nick de Firmian.
[2] The following year Sadvakasov took part in the inaugural FIDE World Cup.
In 2007 he tied for 1st–8th with Hikaru Nakamura, Alexander Shabalov, Varuzhan Akobian, Zviad Izoria, Victor Mikhalevski, Magesh Chandran Panchanathan and Justin Sarkar in the Miami Open.