Truecrypt

[IvanG]

Rolf, we're need only 512 bytes from TrueCrypt volume to start attack. For standard volumes that's 512 bytes from very beginning, so no problem at all to extract everything needed.

gat3way_, when using cascading encryption schemes we're need more output from PBKDF2 function (64 bytes per encryption algorithms, i. e. two 256-bits keys), thus making whole process slower. So limiting encryption algorithms can boost overall performance a lot if you're absolutely sure which algorithm was used.

Effectively, sha512/aes will be about 3x times faster than sha512/aes+twofish+serpent. PBKDF2/RIPEMD/2K iterations should be somewhere near PBKDF2/SHA512/1K speed while whirlpool looks like most GPU unfriendly algorithm here. Unless bitsliced version will be applicable.