No, tower cases do not always come with a power supply. Sometimes they come with a standard one, but many people prefer to choose their own.
You can get a decent tower case with a power supply for 35$.If you don't need a PSU you can get a Tower case for 20$.
Honestly it's just the size. The mid tower will usually have a more robust power supply, because you can fit more devices (such as CD-Rom drives) in the case that needs power.
Drive cases don't usually come with a tower case.However the same companies will sell both and you can get one of each for around 35$ for a tower case(with a power supply)and about 20$ for a drive case.
Aside from server cases the largest number of hard drives you can put into a case appears to be six.That would require an enormous power supply as well.The Lian Li Armorsuit PC-P80 comes with a 1000 watt power supply.
The power supply is usually always located at the top of the computer tower, to the back. Whats easy to find is whatever your power cord from the wall plugs into on the back of your computer, is your power supply box. From there, the power is reduced and sent throughout the computers hardware. (You'll also see that its the box with all the wires are coming out of, inside the computer)
The power supply unit must be toasted.
Full Tower PC Cases are taller than the normal PC Cases (Mid Tower).
E machines do not have a power switch located by the power supply box. They only have the power button in front of tower.
The Cooler Master Storm Scout doesn't come with a power supply. You'll have to buy your own.
The tower houses the motherboard and add-on cards such as the display card and the network card, and also storage such as hard drives, and CD drives. Then it also houses the power supply, which provides power to the above mentioned components.
Most tower cases are constructed of both metal and plastic.
The system unit is the part of the computer that holds the motherboard, power supply and storage. The different types of system units are desktop, tower, mini-tower and notebook.