je ne fais qu´un copier coller et j´ai trouvé ca sur un NG.
open up \baseq3\pak6.pk3 in winzip, extract the file "four.dm_66"
save it to \baseq3\demos (if u dont have a demos folder just make one)
rename the newly extracted file to four.dm_67
load up q3 and timedemo
\timedemo 1
merci Alkor