micro computers architecture

1. MEMORY UPGRADE

2. INTRODUCTION
• The Issues Surrounding Memory
1. Memory Speed
2. Ease of Use and Upgrade
3. Economy
• VRAM ?
• What to Buy and Where to Plug-in ?
• Topics of This Chapter
1. Types of RAM Chips (DIL, SIMM, SIP Etc)
2. RAM Speed Revisited
3. Memory Banks
4. Main-board or Expansion Board
5. Increasing Cache

3. TYPES OF RAM CHIPS
• Chip Capacities
1. 256 K
2. 1 M
3. 4 M
4. 8 M
5. 16 M
• Parity
• DIL : the One Chip Memory
• Static and Handling precautions
• SIMM and SIP Modules are
1. Compact
2. Easy to install
3. Reliable
4. Easily expandable
SIMMs can be
1. Push-in
2. Rotary

4. RAM SPEED REVISITED
•Slow devices are
100-150 ns
and fast devices are
60-80 ns
•POST - Power Self Test
•Sometimes machine has to inform about specs of memory via jumpers
•Main board or expansion board
•For 32 bit expansion use MCA or EISA bus

5. MEMORY BANKS
•Requirement of Byte-wide memory
•BANK - “the smallest chunk of memory that can be added
to a machine is called a bank.”
•Usually for sockets make one bank
•Always ask for documentation while buying any hardware
•Cache memory can also be increased