When you don’t have a TPM chip
Built a computer for Dad that is a small ATX form factor. Found out the motherboard didn’t support a TPM chip. Rats.
So right now testing out Symantec full drive encryption (no true crypt here). Sophos firm encryption is a consideration for someone wanted to roll out cross platform encryption.
I personally have not found encryption to nail the CPU or show any impact on the machine. Granted it does just a little bit during the initial encryption, but after that I’m not seeing a hit.