Tournaments he has won or shared first include the 1969 Swedish Chess Championship, Göteborg 1971, Dortmund 1973, Camagüez 1974, Cienfuegos 1975, Belgrade 1977, Buenos Aires 1978, Hastings 1978–79, Phillips & Drew 1980, Johannesburg 1981, Phillips & Drew 1982, Turin 1982, Wijk aan Zee 1983, Reggio Emilia 1985, Rome 1985, and Rome 1986.
Benny Andersson | Ulf Lundell | Ulf Kristersson | Johan Gunnar Andersson | Jessica Andersson | Ulf Schirmer | Ulf Pilgaard | Ulf Herman | Ulf Hannerz | Ulf Grenander | Ulf Ekman | Ulf Ekberg | Ulf-Dietrich Reips | Ulf Dageby | Sven Andersson | Dan Andersson | Christoffer Andersson | Ulf Malmros | Ulf Lundin | Ulf Långbacka | Ulf Kjell Gür | Ulf Johansson | Ulf Fase | Ulf Andersson | Sven Andersson (politician) | Stig L. Andersson | Sandnes Ulf | Mikael Andersson (footballer born 1978) | Kent-Erik Andersson | Johan A. Andersson |
Over the course of his career, Csom defeated many top Grandmasters, including Ulf Andersson, Boris Gulko, Tony Miles, Lajos Portisch, Samuel Reshevsky, Nigel Short, former World Champion Mikhail Tal, Rafael Vaganian, and Arthur Yussupov.