Differences in PC Types
Computers are available in different shapes and sizes:
Laptop, tower, mini tower, midi tower, full tower, desktop, server case, 'easy pc'
These are usually referred to as the 'form factor'. The form factor dictates the shape and size of the computers innards and more often relates to the dimensions of the motherboard.
AT (large keyboard port, serial mouse), ATX (small - ps2 keyboard and mouse port), Micro ATX, LPS, LPX are common form factors for motherboards and these may be found in any of the case styles mentioned above.
We can generalise pc types to just 2 terms: proprietary and clone
A proprietary computer is designed and manufactured in house, the motherboard is produced using chipsets and circuitry bought in as components. Motherboard form factors can be LPS or LPX, but are often the manufacturers own style. Often the case is unique to that model type or computer firm. Characteristics are horizontally fitting expansion cards, connectivity is built into the motherboard and slim-line cases are used.
Typical proprietary firms are: Compaq, Dell, Elonex, Acer, Packard Bell
Potentially more reliable as there are less internal connections, faster to mass produce - hundreds built per day. Driver availability and customer support is usually excellent. Often bought by businesses as part of an 'IT Solution'
More expensive, difficult to fix, limited expansion, limited upgrade path. Customer is tied to the manufacturer for the life of the machine
A clone computer uses standard form factors: ATX or Micro ATX. The case allows for interchangeable parts: motherboard - all screw holes will line up, graphics cards, expansion cards, drive bays. Most clone manufactures are really kit builders and will buy in modular components from varying sources. When an enthusiast builds a computer it will be a clone.
Typical clone firms are: Time, Mesh, Prospro, Stone, Aria, CCL, Dan
Cheap, easy expansion, easy repair, easy to customise, universal source of parts
Less reliable, manufacturers often buy parts on cost over quality; warranties can be split over different suppliers for components. Poor documentation