Hypothetically,can the boot time of a PC be calculated if the method of encryption,hash,password length,PIM(specific to veracrypt) and PC specs are known?

Assume someone uses the AES-TwoFish-Serpent encryption with SHA-512 and a 60 character password(no word from dictionary,no character repeated,lowercase-uppercase alphanumeric and symbols.) with a 5 digit PIM value. Assume the specs are 2.4GHz processor,1 TB HDD and 8 GB RAM for a relatively new machine.

What will be the approximate boot time in such case? The veracrypt documentation states that higher PIM value will lead to slower mount and 3-layered encryption will slow this even more.Is there some estimation of boot time?

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  • "Assume the specs are 2.4GHz processor,1 TB HDD and 8 GB RAM for a relatively new machine." Was that a joke? I just rebooted my 2009 PC, which has similar specs, although I initially put a 90 GB SSD and 2 TB green drive in it... OK, the 8 GB was largish for the time. I just added a desktop because the laptop that I bought a few years back has similar specs. And I got a dual core CPU at 3.5 GHz for 18 euro on ebay kinda site. Likewise, Linus tech tips had a "El Cheapo" gaming PC with an SSD, because the HDD option was more expensive. – Maarten Bodewes Aug 25 at 16:22

We don't know as there are many more variables to take into account. How fast does the BIOS start, for instance (enable HW RAID for "fun" differences). Which operating system is present? What is the spin-up time of the HDD (if that is still used, they must have forgotten about SSD's for the last 10 years if they do). Does the OS maybe need to perform some updates? If Windows is used, what is the size of the registry? Are there any enhancements such as flash available to the system? Are there applications that are started in the background, requiring access to the disk? Similar for services (which usually require to be started before the OS boots).

So no, we don't really know how to calculate it. Of course the key derivation depends on the parameters of the Password Based Key Derivation Function (PBKDF) so usually that's at least a constant time for a specific implementation and CPU. But really, it is better to setup to similar systems (or one system with two similar bootup drives) and compare a few runs to take out the more or less random differences in bootup. I'd take out the network cable to at least avoid random updates (although that may lead to random time outs, ain't computers fun?).

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