Upgrading and Repairing PCs

1. Upgrading and Repairing PCs Chapter 3

2. Processor Overview: ch 3 • Brain of the PC • Intel, AMD, Cyrix, and Alpha are popular manufacturers • Speed is measured in MHz (megahertz) and soon GHz (Gigahertz) • Performance measured by speed (Mhz) and width (bus width)

3. Processor Specifications • Data Bus • Used to receive and transmit data • Internal Registers • Area for processor to calculate data • Memory Address Bus • Carries addressing information concerning where data is being sent or received from RAM

4. Processor Modes • Real Mode • 16 bit instructions/use only 1MB of memory • Protected Mode • 32 bit instructions/applications run in protected memory spaces • Virtual Real Mode • Used in Windows for backwards compatibility

5. Processor Features • SMM (System Management Mode) • Power Mgmt. Standard used in portables • Superscalar Execution • Execute multiple instructions simultaneously

6. Processor Features • MMX (Multi Media eXtensions) • Improves video, imaging, and I/O processing • Dynamic Execution • Anticipates a programs needs before hand • DIB Architecture (Dual Independent Bus) • Separate busses for memory access

7. Processor Features • L1 cache • Built into CPU • As fast as CPU, 90% success rate • L2 cache • Previously, always located on motherboard • Faster than RAM, slower than CPU • 90% success rate • Trend: locating on CPU • Smaller faster cache better than slower bigger cache

8. Most Common Processor Sockets • Socket 7 • Used by Pentium and Pentium MMX • Still being used by AMD and Cyrix under the name Super 7 • Slot 1 - Used by Pentium II. Looks like a cartridge • Cache mounted in slot for faster access • Not used by any other manufacturer