1. Computer Systems Nat 4/5 Computing Science Types of Computer and Performance

2. Lesson Aims By the end of this lesson:  Pupils at Nat 4 level will be able to: Describe and use clock speed as an indicator of performance Pupils aiming for Nat 5 will be able to Describe the uses of embedded, smartphone, laptop, desktop and supercomputers. Compare features of embedded, smartphone, laptop, desktop and mainframe computers: Discuss the type and speed of processors

3. Clock Speed  Clock speed is the simplest measure of performance  This is the amount of operations that the computer can perform in one second  Modern home CPU’s operate in the 2.4-3.2 GHz range  This means at least 2,400,000,000 instructions per second Nat 4/5

4. Speed isn't everything  Some processors have 2, four or six cores  2,3,4,6, 8 or 16 cores are the usual options  This means that there are 2, 4 or 6 smaller processors built into a single processor.  Each core can work on a single instruction  The faster the processor the more heat they generate. Nat 4/5 So which is better? Dual core at 3.5Ghz or Quad core at 2.4Ghz? So which is better? Dual core at 3.5Ghz or Quad core at 2.4Ghz?

5. Sometimes power is key  Other processors might need a very low power usage  For example using in netbooks, mobile phones or other portable devices. Nat 4/5

6. Apples and Oranges  When comparing performance it helps if the processors are of similar type etc.  For example you cannot compare the clock speed of a Dual Core processor to that of a Quad core processor.  The fastest supercomputer only has a clock speed of 1.6 Ghz (but it does have1,572,864 of them!)  1.6 Pb of RAM might help too! Nat 4/5

7. Types of Computer  As technology improves the types of computer produced change.  Social factors also change types of popular computers  For example laptop sales in the last few years have surpassed desktops.  There are an increase in smart phones  And almost every piece of equipment will have a computer ‘ embedded ’ inside it Nat 4/5

8. Different Types of Computer  For each type of system you need to identify:  The features of the computer system, a purpose for each system, advantages and disadvantages for each system. Nat 4/5 Desktop Laptop Smartphone Tablet Mainframe Embedded

9. Moore's Law  In 1965 the co-founder of Intel(Gordon Moore) made a prediction that:  “The number of transistors incorporated in a chip will approximately double every 24 months.”  So far this ‘law’ has held true but there are physical limits that will be reached.  Current processors are manufactured using 32 nanometre transistors (switches)  Intel has developed transistors so small that about 200 million of them could fit on the head of a pin Nat 4/5

10. Summary  You need to be familiar with the following types of computers  Embedded, laptop, desktop, supercomputer and smartphone  And compare them in terms of:  Type and speed of processor  Size of main memory  Backing storage  Input and output devices Nat 4/5